https://github.com/lessfish/leetcode

【NO LONGER UPDATE】:pencil2: LeetCode solutions with JavaScript
https://github.com/lessfish/leetcode

javascript leetcode leetcode-solutions

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【NO LONGER UPDATE】:pencil2: LeetCode solutions with JavaScript

• Host: GitHub
• URL: https://github.com/lessfish/leetcode
• Owner: lessfish
• Created: 2015-08-09T02:37:24.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2023-01-14T02:46:56.000Z (almost 2 years ago)
• Last Synced: 2024-12-01T06:36:48.154Z (12 days ago)
• Topics: javascript, leetcode, leetcode-solutions
• Language: JavaScript
• Homepage:
• Size: 625 KB
• Stars: 1,554
• Watchers: 74
• Forks: 311
• Open Issues: 3
• Metadata Files:
  • Readme: readme.md
  • Contributing: CONTRIBUTING.md

Awesome Lists containing this project

• awesome-github-star - leetcode
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README

        
# Leetcode Solutions with JavaScript [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](CONTRIBUTING.md)

Update time: Tue Dec 26 2017 22:27:14 GMT+0800 (CST)

I have solved **350 / 668** problems while **124** problems are still locked.

(Notes: :blue_book: means you need to buy a book from Leetcode)

| # | Title | Source Code | Explanation | Difficulty |

|:---:|:---:|:---:|:---:|:---:|

| 754 | [Cracking the Safe](https://leetcode.com/problems/cracking-the-safe/) | | | Hard |

| 753 | [Open the Lock](https://leetcode.com/problems/open-the-lock/) | | | Medium |

| 752 | [IP to CIDR](https://leetcode.com/problems/ip-to-cidr/) | | | Medium |

| 751 | [Number Of Corner Rectangles](https://leetcode.com/problems/number-of-corner-rectangles/) :blue_book: | | | Medium |

| 750 | [Contain Virus](https://leetcode.com/problems/contain-virus/) | | | Hard |

| 749 | [Shortest Completing Word](https://leetcode.com/problems/shortest-completing-word/) | | | Medium |

| 748 | [Largest Number Greater Than Twice of Others](https://leetcode.com/problems/largest-number-greater-than-twice-of-others/) | | | Easy |

| 747 | [Min Cost Climbing Stairs](https://leetcode.com/problems/min-cost-climbing-stairs/) | | | Easy |

| 746 | [Prefix and Suffix Search](https://leetcode.com/problems/prefix-and-suffix-search/) | | | Hard |

| 745 | [Find Smallest Letter Greater Than Target](https://leetcode.com/problems/find-smallest-letter-greater-than-target/) | | | Easy |

| 744 | [Network Delay Time](https://leetcode.com/problems/network-delay-time/) | | | Medium |

| 743 | [Closest Leaf in a Binary Tree](https://leetcode.com/problems/closest-leaf-in-a-binary-tree/) :blue_book: | | | Medium |

| 741 | [Cherry Pickup](https://leetcode.com/problems/cherry-pickup/) | | | Hard |

| 740 | [Delete and Earn](https://leetcode.com/problems/delete-and-earn/) | | | Medium |

| 739 | [Daily Temperatures](https://leetcode.com/problems/daily-temperatures/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Daily%20Temperatures/daily-temperatures.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Daily%20Temperatures/daily-temperatures.py) | | Medium |

| 738 | [Monotone Increasing Digits](https://leetcode.com/problems/monotone-increasing-digits/) | | | Medium |

| 737 | [Sentence Similarity II](https://leetcode.com/problems/sentence-similarity-ii/) :blue_book: | | | Medium |

| 736 | [Parse Lisp Expression](https://leetcode.com/problems/parse-lisp-expression/) | | | Hard |

| 735 | [Asteroid Collision](https://leetcode.com/problems/asteroid-collision/) | | | Medium |

| 734 | [Sentence Similarity](https://leetcode.com/problems/sentence-similarity/) :blue_book: | | | Easy |

| 733 | [Flood Fill](https://leetcode.com/problems/flood-fill/) | | | Easy |

| 732 | [My Calendar III](https://leetcode.com/problems/my-calendar-iii/) | | | Hard |

| 731 | [My Calendar II](https://leetcode.com/problems/my-calendar-ii/) | | | Medium |

| 730 | [Count Different Palindromic Subsequences](https://leetcode.com/problems/count-different-palindromic-subsequences/) | | | Hard |

| 729 | [My Calendar I](https://leetcode.com/problems/my-calendar-i/) | | | Medium |

| 728 | [Self Dividing Numbers](https://leetcode.com/problems/self-dividing-numbers/) | | | Easy |

| 727 | [Minimum Window Subsequence](https://leetcode.com/problems/minimum-window-subsequence/) :blue_book: | | | Hard |

| 726 | [Number of Atoms](https://leetcode.com/problems/number-of-atoms/) | | | Hard |

| 725 | [Split Linked List in Parts](https://leetcode.com/problems/split-linked-list-in-parts/) | | | Medium |

| 724 | [Find Pivot Index](https://leetcode.com/problems/find-pivot-index/) | | | Easy |

| 723 | [Candy Crush](https://leetcode.com/problems/candy-crush/) :blue_book: | | | Medium |

| 722 | [Remove Comments](https://leetcode.com/problems/remove-comments/) | | | Medium |

| 721 | [Accounts Merge](https://leetcode.com/problems/accounts-merge/) | | | Medium |

| 720 | [Longest Word in Dictionary](https://leetcode.com/problems/longest-word-in-dictionary/) | | | Easy |

| 719 | [Find K-th Smallest Pair Distance](https://leetcode.com/problems/find-k-th-smallest-pair-distance/) | | | Hard |

| 718 | [Maximum Length of Repeated Subarray](https://leetcode.com/problems/maximum-length-of-repeated-subarray/) | | | Medium |

| 717 | [1-bit and 2-bit Characters](https://leetcode.com/problems/1-bit-and-2-bit-characters/) | | | Easy |

| 716 | [Max Stack](https://leetcode.com/problems/max-stack/) :blue_book: | | | Hard |

| 715 | [Range Module](https://leetcode.com/problems/range-module/) | | | Hard |

| 714 | [Best Time to Buy and Sell Stock with Transaction Fee](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee/) | | | Medium |

| 713 | [Subarray Product Less Than K](https://leetcode.com/problems/subarray-product-less-than-k/) | | | Medium |

| 712 | [Minimum ASCII Delete Sum for Two Strings](https://leetcode.com/problems/minimum-ascii-delete-sum-for-two-strings/) | | | Medium |

| 711 | [Number of Distinct Islands II](https://leetcode.com/problems/number-of-distinct-islands-ii/) :blue_book: | | | Hard |

| 699 | [Falling Squares](https://leetcode.com/problems/falling-squares/) | | | Hard |

| 698 | [Partition to K Equal Sum Subsets](https://leetcode.com/problems/partition-to-k-equal-sum-subsets/) | | | Medium |

| 697 | [Degree of an Array](https://leetcode.com/problems/degree-of-an-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Degree%20of%20an%20Array/degree-of-an-array.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Degree%20of%20an%20Array/degree-of-an-array.py) | | Easy |

| 696 | [Count Binary Substrings](https://leetcode.com/problems/count-binary-substrings/) | | | Easy |

| 695 | [Max Area of Island](https://leetcode.com/problems/max-area-of-island/) | | | Easy |

| 694 | [Number of Distinct Islands](https://leetcode.com/problems/number-of-distinct-islands/) :blue_book: | | | Medium |

| 693 | [Binary Number with Alternating Bits](https://leetcode.com/problems/binary-number-with-alternating-bits/) | | | Easy |

| 692 | [Top K Frequent Words](https://leetcode.com/problems/top-k-frequent-words/) | | | Medium |

| 691 | [Stickers to Spell Word](https://leetcode.com/problems/stickers-to-spell-word/) | | | Hard |

| 690 | [Employee Importance](https://leetcode.com/problems/employee-importance/) | | | Easy |

| 689 | [Maximum Sum of 3 Non-Overlapping Subarrays](https://leetcode.com/problems/maximum-sum-of-3-non-overlapping-subarrays/) | | | Hard |

| 688 | [Knight Probability in Chessboard](https://leetcode.com/problems/knight-probability-in-chessboard/) | | | Medium |

| 687 | [Longest Univalue Path](https://leetcode.com/problems/longest-univalue-path/) | | | Easy |

| 686 | [Repeated String Match](https://leetcode.com/problems/repeated-string-match/) | | | Easy |

| 685 | [Redundant Connection II](https://leetcode.com/problems/redundant-connection-ii/) | | | Hard |

| 684 | [Redundant Connection](https://leetcode.com/problems/redundant-connection/) | | | Medium |

| 683 | [K Empty Slots](https://leetcode.com/problems/k-empty-slots/) :blue_book: | | | Hard |

| 682 | [Baseball Game](https://leetcode.com/problems/baseball-game/) | | | Easy |

| 681 | [Next Closest Time](https://leetcode.com/problems/next-closest-time/) :blue_book: | | | Medium |

| 680 | [Valid Palindrome II](https://leetcode.com/problems/valid-palindrome-ii/) | | | Easy |

| 679 | [24 Game](https://leetcode.com/problems/24-game/) | | | Hard |

| 678 | [Valid Parenthesis String](https://leetcode.com/problems/valid-parenthesis-string/) | | | Medium |

| 677 | [Map Sum Pairs](https://leetcode.com/problems/map-sum-pairs/) | | | Medium |

| 676 | [Implement Magic Dictionary](https://leetcode.com/problems/implement-magic-dictionary/) | | | Medium |

| 675 | [Cut Off Trees for Golf Event](https://leetcode.com/problems/cut-off-trees-for-golf-event/) | | | Hard |

| 674 | [Longest Continuous Increasing Subsequence](https://leetcode.com/problems/longest-continuous-increasing-subsequence/) | | | Easy |

| 673 | [Number of Longest Increasing Subsequence](https://leetcode.com/problems/number-of-longest-increasing-subsequence/) | | | Medium |

| 672 | [Bulb Switcher II](https://leetcode.com/problems/bulb-switcher-ii/) | | | Medium |

| 671 | [Second Minimum Node In a Binary Tree](https://leetcode.com/problems/second-minimum-node-in-a-binary-tree/) | | | Easy |

| 670 | [Maximum Swap](https://leetcode.com/problems/maximum-swap/) | | | Medium |

| 669 | [Trim a Binary Search Tree](https://leetcode.com/problems/trim-a-binary-search-tree/) | | | Easy |

| 668 | [Kth Smallest Number in Multiplication Table](https://leetcode.com/problems/kth-smallest-number-in-multiplication-table/) | | | Hard |

| 667 | [Beautiful Arrangement II](https://leetcode.com/problems/beautiful-arrangement-ii/) | | | Medium |

| 666 | [Path Sum IV](https://leetcode.com/problems/path-sum-iv/) :blue_book: | | | Medium |

| 665 | [Non-decreasing Array](https://leetcode.com/problems/non-decreasing-array/) | | | Easy |

| 664 | [Strange Printer](https://leetcode.com/problems/strange-printer/) | | | Hard |

| 663 | [Equal Tree Partition](https://leetcode.com/problems/equal-tree-partition/) :blue_book: | | | Medium |

| 662 | [Maximum Width of Binary Tree](https://leetcode.com/problems/maximum-width-of-binary-tree/) | | | Medium |

| 661 | [Image Smoother](https://leetcode.com/problems/image-smoother/) | | | Easy |

| 660 | [Remove 9](https://leetcode.com/problems/remove-9/) :blue_book: | | | Hard |

| 659 | [Split Array into Consecutive Subsequences](https://leetcode.com/problems/split-array-into-consecutive-subsequences/) | | | Medium |

| 658 | [Find K Closest Elements](https://leetcode.com/problems/find-k-closest-elements/) | | | Medium |

| 657 | [Judge Route Circle](https://leetcode.com/problems/judge-route-circle/) | | | Easy |

| 656 | [Coin Path](https://leetcode.com/problems/coin-path/) :blue_book: | | | Hard |

| 655 | [Print Binary Tree](https://leetcode.com/problems/print-binary-tree/) | | | Medium |

| 654 | [Maximum Binary Tree](https://leetcode.com/problems/maximum-binary-tree/) | | | Medium |

| 653 | [Two Sum IV - Input is a BST](https://leetcode.com/problems/two-sum-iv-input-is-a-bst/) | | | Easy |

| 652 | [Find Duplicate Subtrees](https://leetcode.com/problems/find-duplicate-subtrees/) | | | Medium |

| 651 | [4 Keys Keyboard](https://leetcode.com/problems/4-keys-keyboard/) :blue_book: | | | Medium |

| 650 | [2 Keys Keyboard](https://leetcode.com/problems/2-keys-keyboard/) | | | Medium |

| 649 | [Dota2 Senate](https://leetcode.com/problems/dota2-senate/) | | | Medium |

| 648 | [Replace Words](https://leetcode.com/problems/replace-words/) | | | Medium |

| 647 | [Palindromic Substrings](https://leetcode.com/problems/palindromic-substrings/) | | | Medium |

| 646 | [Maximum Length of Pair Chain](https://leetcode.com/problems/maximum-length-of-pair-chain/) | | | Medium |

| 645 | [Set Mismatch](https://leetcode.com/problems/set-mismatch/) | | | Easy |

| 644 | [Maximum Average Subarray II](https://leetcode.com/problems/maximum-average-subarray-ii/) :blue_book: | | | Hard |

| 643 | [Maximum Average Subarray I](https://leetcode.com/problems/maximum-average-subarray-i/) | | | Easy |

| 642 | [Design Search Autocomplete System](https://leetcode.com/problems/design-search-autocomplete-system/) :blue_book: | | | Hard |

| 640 | [Solve the Equation](https://leetcode.com/problems/solve-the-equation/) | | | Medium |

| 639 | [Decode Ways II](https://leetcode.com/problems/decode-ways-ii/) | | | Hard |

| 638 | [Shopping Offers](https://leetcode.com/problems/shopping-offers/) | | | Medium |

| 637 | [Average of Levels in Binary Tree](https://leetcode.com/problems/average-of-levels-in-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Average%20of%20Levels%20in%20Binary%20Tree/average-of-levels-in-binary-tree.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Average%20of%20Levels%20in%20Binary%20Tree/average-of-levels-in-binary-tree.py) | | Easy |

| 636 | [Exclusive Time of Functions](https://leetcode.com/problems/exclusive-time-of-functions/) | | | Medium |

| 635 | [Design Log Storage System](https://leetcode.com/problems/design-log-storage-system/) :blue_book: | | | Medium |

| 634 | [Find the Derangement of An Array](https://leetcode.com/problems/find-the-derangement-of-an-array/) :blue_book: | | | Medium |

| 633 | [Sum of Square Numbers](https://leetcode.com/problems/sum-of-square-numbers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sum%20of%20Square%20Numbers/sum-of-square-numbers.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sum%20of%20Square%20Numbers/sum-of-square-numbers.py) | | Easy |

| 632 | [Smallest Range](https://leetcode.com/problems/smallest-range/) | | | Hard |

| 631 | [Design Excel Sum Formula](https://leetcode.com/problems/design-excel-sum-formula/) :blue_book: | | | Hard |

| 630 | [Course Schedule III](https://leetcode.com/problems/course-schedule-iii/) | | | Hard |

| 629 | [K Inverse Pairs Array](https://leetcode.com/problems/k-inverse-pairs-array/) | | | Hard |

| 628 | [Maximum Product of Three Numbers](https://leetcode.com/problems/maximum-product-of-three-numbers/) | | | Easy |

| 625 | [Minimum Factorization](https://leetcode.com/problems/minimum-factorization/) :blue_book: | | | Medium |

| 624 | [Maximum Distance in Arrays](https://leetcode.com/problems/maximum-distance-in-arrays/) :blue_book: | | | Easy |

| 623 | [Add One Row to Tree](https://leetcode.com/problems/add-one-row-to-tree/) | | | Medium |

| 621 | [Task Scheduler](https://leetcode.com/problems/task-scheduler/) | | | Medium |

| 617 | [Merge Two Binary Trees](https://leetcode.com/problems/merge-two-binary-trees/) | | | Easy |

| 616 | [Add Bold Tag in String](https://leetcode.com/problems/add-bold-tag-in-string/) :blue_book: | | | Medium |

| 611 | [Valid Triangle Number](https://leetcode.com/problems/valid-triangle-number/) | | | Medium |

| 609 | [Find Duplicate File in System](https://leetcode.com/problems/find-duplicate-file-in-system/) | | | Medium |

| 606 | [Construct String from Binary Tree](https://leetcode.com/problems/construct-string-from-binary-tree/) | | | Easy |

| 605 | [Can Place Flowers](https://leetcode.com/problems/can-place-flowers/) | | | Easy |

| 604 | [Design Compressed String Iterator](https://leetcode.com/problems/design-compressed-string-iterator/) :blue_book: | | | Easy |

| 600 | [Non-negative Integers without Consecutive Ones](https://leetcode.com/problems/non-negative-integers-without-consecutive-ones/) | | | Hard |

| 599 | [Minimum Index Sum of Two Lists](https://leetcode.com/problems/minimum-index-sum-of-two-lists/) | | | Easy |

| 598 | [Range Addition II](https://leetcode.com/problems/range-addition-ii/) | | | Easy |

| 594 | [Longest Harmonious Subsequence](https://leetcode.com/problems/longest-harmonious-subsequence/) | | | Easy |

| 593 | [Valid Square](https://leetcode.com/problems/valid-square/) | | | Medium |

| 592 | [Fraction Addition and Subtraction](https://leetcode.com/problems/fraction-addition-and-subtraction/) | | | Medium |

| 591 | [Tag Validator](https://leetcode.com/problems/tag-validator/) | | | Hard |

| 588 | [Design In-Memory File System](https://leetcode.com/problems/design-in-memory-file-system/) :blue_book: | | | Hard |

| 587 | [Erect the Fence](https://leetcode.com/problems/erect-the-fence/) | | | Hard |

| 583 | [Delete Operation for Two Strings](https://leetcode.com/problems/delete-operation-for-two-strings/) | | | Medium |

| 582 | [Kill Process](https://leetcode.com/problems/kill-process/) :blue_book: | | | Medium |

| 581 | [Shortest Unsorted Continuous Subarray](https://leetcode.com/problems/shortest-unsorted-continuous-subarray/) | | | Easy |

| 576 | [Out of Boundary Paths](https://leetcode.com/problems/out-of-boundary-paths/) | | | Medium |

| 575 | [Distribute Candies](https://leetcode.com/problems/distribute-candies/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Distribute%20Candies/distribute-candies.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Distribute%20Candies/distribute-candies.py) | | Easy |

| 573 | [Squirrel Simulation](https://leetcode.com/problems/squirrel-simulation/) :blue_book: | | | Medium |

| 572 | [Subtree of Another Tree](https://leetcode.com/problems/subtree-of-another-tree/) | | | Easy |

| 568 | [Maximum Vacation Days](https://leetcode.com/problems/maximum-vacation-days/) :blue_book: | | | Hard |

| 567 | [Permutation in String](https://leetcode.com/problems/permutation-in-string/) | | | Medium |

| 566 | [Reshape the Matrix](https://leetcode.com/problems/reshape-the-matrix/) | | | Easy |

| 565 | [Array Nesting](https://leetcode.com/problems/array-nesting/) | | | Medium |

| 564 | [Find the Closest Palindrome](https://leetcode.com/problems/find-the-closest-palindrome/) | | | Hard |

| 563 | [Binary Tree Tilt](https://leetcode.com/problems/binary-tree-tilt/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Tilt/binary-tree-tilt.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Tilt/binary-tree-tilt.py) | | Easy |

| 562 | [Longest Line of Consecutive One in Matrix](https://leetcode.com/problems/longest-line-of-consecutive-one-in-matrix/) :blue_book: | | | Medium |

| 561 | [Array Partition I](https://leetcode.com/problems/array-partition-i/) | | | Easy |

| 560 | [Subarray Sum Equals K](https://leetcode.com/problems/subarray-sum-equals-k/) | | | Medium |

| 557 | [Reverse Words in a String III](https://leetcode.com/problems/reverse-words-in-a-string-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Words%20in%20a%20String%20III/reverse-words-in-a-string-iii.js) [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Words%20in%20a%20String%20III/reverse-words-in-a-string-iii.py) | | Easy |

| 556 | [Next Greater Element III](https://leetcode.com/problems/next-greater-element-iii/) | | | Medium |

| 555 | [Split Concatenated Strings](https://leetcode.com/problems/split-concatenated-strings/) :blue_book: | | | Medium |

| 554 | [Brick Wall](https://leetcode.com/problems/brick-wall/) | | | Medium |

| 553 | [Optimal Division](https://leetcode.com/problems/optimal-division/) | | | Medium |

| 552 | [Student Attendance Record II](https://leetcode.com/problems/student-attendance-record-ii/) | | | Hard |

| 551 | [Student Attendance Record I](https://leetcode.com/problems/student-attendance-record-i/) | | | Easy |

| 549 | [Binary Tree Longest Consecutive Sequence II](https://leetcode.com/problems/binary-tree-longest-consecutive-sequence-ii/) :blue_book: | | | Medium |

| 548 | [Split Array with Equal Sum](https://leetcode.com/problems/split-array-with-equal-sum/) :blue_book: | | | Medium |

| 547 | [Friend Circles](https://leetcode.com/problems/friend-circles/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Friend%20Circles/friend-circles.py) | | Medium |

| 546 | [Remove Boxes](https://leetcode.com/problems/remove-boxes/) | | | Hard |

| 545 | [Boundary of Binary Tree](https://leetcode.com/problems/boundary-of-binary-tree/) :blue_book: | | | Medium |

| 544 | [Output Contest Matches](https://leetcode.com/problems/output-contest-matches/) :blue_book: | | | Medium |

| 543 | [Diameter of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Diameter%20of%20Binary%20Tree/diameter-of-binary-tree.py) | | Easy |

| 542 | [01 Matrix](https://leetcode.com/problems/01-matrix/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/01%20Matrix/01-matrix.js) | | Medium |

| 541 | [Reverse String II](https://leetcode.com/problems/reverse-string-ii/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20String%20II/reverse-string-ii.py) | | Easy |

| 540 | [Single Element in a Sorted Array](https://leetcode.com/problems/single-element-in-a-sorted-array/) | | | Medium |

| 539 | [Minimum Time Difference](https://leetcode.com/problems/minimum-time-difference/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Time%20Difference/minimum-time-difference.js) | | Medium |

| 538 | [Convert BST to Greater Tree](https://leetcode.com/problems/convert-bst-to-greater-tree/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Convert%20BST%20to%20Greater%20Tree/convert-bst-to-greater-tree.py) | | Easy |

| 537 | [Complex Number Multiplication](https://leetcode.com/problems/complex-number-multiplication/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Complex%20Number%20Multiplication/complex-number-multiplication.py) | | Medium |

| 536 | [Construct Binary Tree from String](https://leetcode.com/problems/construct-binary-tree-from-string/) :blue_book: | | | Medium |

| 535 | [Encode and Decode TinyURL](https://leetcode.com/problems/encode-and-decode-tinyurl/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Encode%20and%20Decode%20TinyURL/encode-and-decode-tinyurl.js) | | Medium |

| 533 | [Lonely Pixel II](https://leetcode.com/problems/lonely-pixel-ii/) :blue_book: | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Lonely%20Pixel%20II/lonely-pixel-ii.py) | | Medium |

| 532 | [K-diff Pairs in an Array](https://leetcode.com/problems/k-diff-pairs-in-an-array/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/K-diff%20Pairs%20in%20an%20Array/k-diff-pairs-in-an-array.py) | | Easy |

| 531 | [Lonely Pixel I](https://leetcode.com/problems/lonely-pixel-i/) :blue_book: | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Lonely%20Pixel%20I/lonely-pixel-i.py) | | Medium |

| 530 | [Minimum Absolute Difference in BST](https://leetcode.com/problems/minimum-absolute-difference-in-bst/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Absolute%20Difference%20in%20BST/minimum-absolute-difference-in-bst.py) | | Easy |

| 529 | [Minesweeper](https://leetcode.com/problems/minesweeper/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minesweeper/minesweeper.py) | | Medium |

| 527 | [Word Abbreviation](https://leetcode.com/problems/word-abbreviation/) :blue_book: | | | Hard |

| 526 | [Beautiful Arrangement](https://leetcode.com/problems/beautiful-arrangement/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Beautiful%20Arrangement/beautiful-arrangement.js) | | Medium |

| 525 | [Contiguous Array](https://leetcode.com/problems/contiguous-array/) | | | Medium |

| 524 | [Longest Word in Dictionary through Deleting](https://leetcode.com/problems/longest-word-in-dictionary-through-deleting/) | | | Medium |

| 523 | [Continuous Subarray Sum](https://leetcode.com/problems/continuous-subarray-sum/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Continuous%20Subarray%20Sum/continuous-subarray-sum.py) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Continuous%20Subarray%20Sum/README.md) | Medium |

| 522 | [Longest Uncommon Subsequence II](https://leetcode.com/problems/longest-uncommon-subsequence-ii/) | | | Medium |

| 521 | [Longest Uncommon Subsequence I ](https://leetcode.com/problems/longest-uncommon-subsequence-i/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Uncommon%20Subsequence%20I%20/longest-uncommon-subsequence-i.py) | | Easy |

| 520 | [Detect Capital](https://leetcode.com/problems/detect-capital/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Detect%20Capital/detect-capital.js) | | Easy |

| 517 | [Super Washing Machines](https://leetcode.com/problems/super-washing-machines/) | | | Hard |

| 516 | [Longest Palindromic Subsequence](https://leetcode.com/problems/longest-palindromic-subsequence/) | | | Medium |

| 515 | [Find Largest Value in Each Tree Row](https://leetcode.com/problems/find-largest-value-in-each-tree-row/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Largest%20Value%20in%20Each%20Tree%20Row/find-largest-value-in-each-tree-row.js) | | Medium |

| 514 | [Freedom Trail](https://leetcode.com/problems/freedom-trail/) | | | Hard |

| 513 | [Find Bottom Left Tree Value](https://leetcode.com/problems/find-bottom-left-tree-value/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Bottom%20Left%20Tree%20Value/find-bottom-left-tree-value.js) | | Medium |

| 508 | [Most Frequent Subtree Sum](https://leetcode.com/problems/most-frequent-subtree-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Most%20Frequent%20Subtree%20Sum/most-frequent-subtree-sum.js) | | Medium |

| 507 | [Perfect Number](https://leetcode.com/problems/perfect-number/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Perfect%20Number/perfect-number.py) | | Easy |

| 506 | [Relative Ranks](https://leetcode.com/problems/relative-ranks/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Relative%20Ranks/relative-ranks.js) | | Easy |

| 505 | [The Maze II](https://leetcode.com/problems/the-maze-ii/) :blue_book: | | | Medium |

| 504 | [Base 7](https://leetcode.com/problems/base-7/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Base%207/base-7.js) | | Easy |

| 503 | [Next Greater Element II](https://leetcode.com/problems/next-greater-element-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Next%20Greater%20Element%20II/diagonal-traverse.js) | | Medium |

| 502 | [IPO](https://leetcode.com/problems/ipo/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/IPO/ipo.js) | | Hard |

| 501 | [Find Mode in Binary Search Tree](https://leetcode.com/problems/find-mode-in-binary-search-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Mode%20in%20Binary%20Search%20Tree/find-mode-in-binary-search-tree.js) | | Easy |

| 500 | [Keyboard Row](https://leetcode.com/problems/keyboard-row/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Keyboard%20Row/keyboard-row.js) | | Easy |

| 499 | [The Maze III](https://leetcode.com/problems/the-maze-iii/) :blue_book: | | | Hard |

| 498 | [Diagonal Traverse](https://leetcode.com/problems/diagonal-traverse/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Diagonal%20Traverse/diagonal-traverse.js) | | Medium |

| 496 | [Next Greater Element I](https://leetcode.com/problems/next-greater-element-i/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Next%20Greater%20Element%20I/next-greater-element-i.js) | | Easy |

| 495 | [Teemo Attacking](https://leetcode.com/problems/teemo-attacking/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Teemo%20Attacking/teemo-attacking.js) | | Medium |

| 494 | [Target Sum](https://leetcode.com/problems/target-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Target%20Sum/dfs-solution.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Target%20Sum/README.md) | Medium |

| 493 | [Reverse Pairs](https://leetcode.com/problems/reverse-pairs/) | | | Hard |

| 492 | [Construct the Rectangle](https://leetcode.com/problems/construct-the-rectangle/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Construct%20the%20Rectangle/construct-the-rectangle.js) | | Easy |

| 491 | [Increasing Subsequences](https://leetcode.com/problems/increasing-subsequences/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Increasing%20Subsequences/use-set.js) | | Medium |

| 490 | [The Maze](https://leetcode.com/problems/the-maze/) :blue_book: | | | Medium |

| 488 | [Zuma Game](https://leetcode.com/problems/zuma-game/) | | | Hard |

| 487 | [Max Consecutive Ones II](https://leetcode.com/problems/max-consecutive-ones-ii/) :blue_book: | | | Medium |

| 486 | [Predict the Winner](https://leetcode.com/problems/predict-the-winner/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Predict%20the%20Winner/predict-the-winner.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Predict%20the%20Winner/README.md) | Medium |

| 485 | [Max Consecutive Ones](https://leetcode.com/problems/max-consecutive-ones/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Max%20Consecutive%20Ones/max-consecutive-ones.js) | | Easy |

| 484 | [Find Permutation](https://leetcode.com/problems/find-permutation/) :blue_book: | | | Medium |

| 483 | [Smallest Good Base](https://leetcode.com/problems/smallest-good-base/) | | | Hard |

| 482 | [License Key Formatting](https://leetcode.com/problems/license-key-formatting/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/License%20Key%20Formatting/license-key-formatting.js) | | Easy |

| 481 | [Magical String](https://leetcode.com/problems/magical-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Magical%20String/magical-string.js) | | Medium |

| 480 | [Sliding Window Median](https://leetcode.com/problems/sliding-window-median/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sliding%20Window%20Median/sliding-window-median.js) | | Hard |

| 479 | [Largest Palindrome Product](https://leetcode.com/problems/largest-palindrome-product/) | | | Easy |

| 477 | [Total Hamming Distance](https://leetcode.com/problems/total-hamming-distance/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Total%20Hamming%20Distance/total-hamming-distance.js) | | Medium |

| 476 | [Number Complement](https://leetcode.com/problems/number-complement/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20Complement/number-complement.js) | | Easy |

| 475 | [Heaters](https://leetcode.com/problems/heaters/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Heaters/heaters.js) | | Easy |

| 474 | [Ones and Zeroes](https://leetcode.com/problems/ones-and-zeroes/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Ones%20and%20Zeroes/ones-and-zeroes.js) | | Medium |

| 473 | [Matchsticks to Square](https://leetcode.com/problems/matchsticks-to-square/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Matchsticks%20to%20Square/matchsticks-to-square.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Matchsticks%20to%20Square/README.md) | Medium |

| 472 | [Concatenated Words](https://leetcode.com/problems/concatenated-words/) | | | Hard |

| 471 | [Encode String with Shortest Length](https://leetcode.com/problems/encode-string-with-shortest-length/) :blue_book: | | | Hard |

| 469 | [Convex Polygon](https://leetcode.com/problems/convex-polygon/) :blue_book: | | | Medium |

| 468 | [Validate IP Address](https://leetcode.com/problems/validate-ip-address/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Validate%20IP%20Address/validate-ip-address.js) | | Medium |

| 467 | [Unique Substrings in Wraparound String](https://leetcode.com/problems/unique-substrings-in-wraparound-string/) | | | Medium |

| 466 | [Count The Repetitions](https://leetcode.com/problems/count-the-repetitions/) | | | Hard |

| 465 | [Optimal Account Balancing](https://leetcode.com/problems/optimal-account-balancing/) :blue_book: | | | Hard |

| 464 | [Can I Win](https://leetcode.com/problems/can-i-win/) | | | Medium |

| 463 | [Island Perimeter](https://leetcode.com/problems/island-perimeter/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Island%20Perimeter/island-perimeter.js) | | Easy |

| 462 | [Minimum Moves to Equal Array Elements II](https://leetcode.com/problems/minimum-moves-to-equal-array-elements-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Moves%20to%20Equal%20Array%20Elements%20II/minimum-moves-to-equal-array-elements-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Moves%20to%20Equal%20Array%20Elements%20II/README.md) | Medium |

| 461 | [Hamming Distance](https://leetcode.com/problems/hamming-distance/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Hamming%20Distance/hamming-distance.js) | | Easy |

| 460 | [LFU Cache](https://leetcode.com/problems/lfu-cache/) | | | Hard |

| 459 | [Repeated Substring Pattern](https://leetcode.com/problems/repeated-substring-pattern/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Repeated%20Substring%20Pattern/repeated-substring-pattern.js) | | Easy |

| 456 | [132 Pattern](https://leetcode.com/problems/132-pattern/) | | | Medium |

| 455 | [Assign Cookies](https://leetcode.com/problems/assign-cookies/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Assign%20Cookies/assign-cookies.js) | | Easy |

| 454 | [4Sum II](https://leetcode.com/problems/4sum-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/4Sum%20II/4sum-ii.js) | | Medium |

| 453 | [Minimum Moves to Equal Array Elements](https://leetcode.com/problems/minimum-moves-to-equal-array-elements/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Moves%20to%20Equal%20Array%20Elements/minimum-moves-to-equal-array-elements.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Moves%20to%20Equal%20Array%20Elements/README.md) | Easy |

| 452 | [Minimum Number of Arrows to Burst Balloons](https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Number%20of%20Arrows%20to%20Burst%20Balloons/minimum-number-of-arrows-to-burst-balloons.js) | | Medium |

| 451 | [Sort Characters By Frequency](https://leetcode.com/problems/sort-characters-by-frequency/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sort%20Characters%20By%20Frequency/sort-characters-by-frequency.js) | | Medium |

| 450 | [Delete Node in a BST](https://leetcode.com/problems/delete-node-in-a-bst/) | | | Medium |

| 449 | [Serialize and Deserialize BST](https://leetcode.com/problems/serialize-and-deserialize-bst/) | | | Medium |

| 448 | [Find All Numbers Disappeared in an Array](https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20All%20Numbers%20Disappeared%20in%20an%20Array/find-all-numbers-disappeared-in-an-array.js) | | Easy |

| 447 | [Number of Boomerangs](https://leetcode.com/problems/number-of-boomerangs/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20of%20Boomerangs/number-of-boomerangs.js) | | Easy |

| 446 | [Arithmetic Slices II - Subsequence](https://leetcode.com/problems/arithmetic-slices-ii-subsequence/) | | | Hard |

| 445 | [Add Two Numbers II](https://leetcode.com/problems/add-two-numbers-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Two%20Numbers%20II/add-two-numbers-ii.js) | | Medium |

| 444 | [Sequence Reconstruction](https://leetcode.com/problems/sequence-reconstruction/) :blue_book: | | | Medium |

| 443 | [String Compression](https://leetcode.com/problems/string-compression/) | | | Easy |

| 442 | [Find All Duplicates in an Array](https://leetcode.com/problems/find-all-duplicates-in-an-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20All%20Duplicates%20in%20an%20Array/find-all-duplicates-in-an-array.js) | | Medium |

| 441 | [Arranging Coins](https://leetcode.com/problems/arranging-coins/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Arranging%20Coins/arranging-coins.js) | | Easy |

| 440 | [K-th Smallest in Lexicographical Order](https://leetcode.com/problems/k-th-smallest-in-lexicographical-order/) | | | Hard |

| 439 | [Ternary Expression Parser](https://leetcode.com/problems/ternary-expression-parser/) :blue_book: | | | Medium |

| 438 | [Find All Anagrams in a String](https://leetcode.com/problems/find-all-anagrams-in-a-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20All%20Anagrams%20in%20a%20String/find-all-anagrams-in-a-string.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20All%20Anagrams%20in%20a%20String/Readme.md) | Easy |

| 437 | [Path Sum III](https://leetcode.com/problems/path-sum-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Path%20Sum%20III/path-sum-iii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Path%20Sum%20III/Readme.md) | Easy |

| 436 | [Find Right Interval](https://leetcode.com/problems/find-right-interval/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Right%20Interval/find-right-interval.js) | | Medium |

| 435 | [Non-overlapping Intervals](https://leetcode.com/problems/non-overlapping-intervals/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Non-overlapping%20Intervals/non-overlapping-intervals.js) | | Medium |

| 434 | [Number of Segments in a String](https://leetcode.com/problems/number-of-segments-in-a-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20of%20Segments%20in%20a%20String/number-of-segments-in-a-string.js) | | Easy |

| 432 | [All O`one Data Structure](https://leetcode.com/problems/all-oone-data-structure/) | | | Hard |

| 425 | [Word Squares](https://leetcode.com/problems/word-squares/) :blue_book: | | | Hard |

| 424 | [Longest Repeating Character Replacement](https://leetcode.com/problems/longest-repeating-character-replacement/) | | | Medium |

| 423 | [Reconstruct Original Digits from English](https://leetcode.com/problems/reconstruct-original-digits-from-english/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reconstruct%20Original%20Digits%20from%20English/reconstruct-original-digits-from-english.js) | | Medium |

| 422 | [Valid Word Square](https://leetcode.com/problems/valid-word-square/) :blue_book: | | | Easy |

| 421 | [Maximum XOR of Two Numbers in an Array](https://leetcode.com/problems/maximum-xor-of-two-numbers-in-an-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20XOR%20of%20Two%20Numbers%20in%20an%20Array/maximum-xor-of-two-numbers-in-an-array.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20XOR%20of%20Two%20Numbers%20in%20an%20Array/README.md) | Medium |

| 420 | [Strong Password Checker](https://leetcode.com/problems/strong-password-checker/) | | | Hard |

| 419 | [Battleships in a Board](https://leetcode.com/problems/battleships-in-a-board/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Battleships%20in%20a%20Board/battleships-in-a-board.js) | | Medium |

| 418 | [Sentence Screen Fitting](https://leetcode.com/problems/sentence-screen-fitting/) :blue_book: | | | Medium |

| 417 | [Pacific Atlantic Water Flow](https://leetcode.com/problems/pacific-atlantic-water-flow/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pacific%20Atlantic%20Water%20Flow/pacific-atlantic-water-flow.js) | | Medium |

| 416 | [Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/) | | | Medium |

| 415 | [Add Strings](https://leetcode.com/problems/add-strings/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Strings/add-strings.js) | | Easy |

| 414 | [Third Maximum Number](https://leetcode.com/problems/third-maximum-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Third%20Maximum%20Number/third-maximum-number.js) | | Easy |

| 413 | [Arithmetic Slices](https://leetcode.com/problems/arithmetic-slices/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Arithmetic%20Slices/arithmetic-slices.js) | | Medium |

| 412 | [Fizz Buzz](https://leetcode.com/problems/fizz-buzz/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Fizz%20Buzz/fizz-buzz.js) | | Easy |

| 411 | [Minimum Unique Word Abbreviation](https://leetcode.com/problems/minimum-unique-word-abbreviation/) :blue_book: | | | Hard |

| 410 | [Split Array Largest Sum](https://leetcode.com/problems/split-array-largest-sum/) | | | Hard |

| 409 | [Longest Palindrome](https://leetcode.com/problems/longest-palindrome/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Palindrome/longest-palindrome.js) | | Easy |

| 408 | [Valid Word Abbreviation](https://leetcode.com/problems/valid-word-abbreviation/) :blue_book: | | | Easy |

| 407 | [Trapping Rain Water II](https://leetcode.com/problems/trapping-rain-water-ii/) | | | Hard |

| 406 | [Queue Reconstruction by Height](https://leetcode.com/problems/queue-reconstruction-by-height/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Queue%20Reconstruction%20by%20Height/queue-reconstruction-by-height.js) | | Medium |

| 405 | [Convert a Number to Hexadecimal](https://leetcode.com/problems/convert-a-number-to-hexadecimal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Convert%20a%20Number%20to%20Hexadecimal/convert-a-number-to-hexadecimal.js) | | Easy |

| 404 | [Sum of Left Leaves](https://leetcode.com/problems/sum-of-left-leaves/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sum%20of%20Left%20Leaves/sum-of-left-leaves.js) | | Easy |

| 403 | [Frog Jump](https://leetcode.com/problems/frog-jump/) | | | Hard |

| 402 | [Remove K Digits](https://leetcode.com/problems/remove-k-digits/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20K%20Digits/remove-k-digits.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20K%20Digits/readme.md) | Medium |

| 401 | [Binary Watch](https://leetcode.com/problems/binary-watch/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Watch/binary-watch.js) | | Easy |

| 400 | [Nth Digit](https://leetcode.com/problems/nth-digit/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Nth%20Digit/nth-digit.js) | | Easy |

| 399 | [Evaluate Division](https://leetcode.com/problems/evaluate-division/) | | | Medium |

| 398 | [Random Pick Index](https://leetcode.com/problems/random-pick-index/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Random%20Pick%20Index/random-pick-index.py) | | Medium |

| 397 | [Integer Replacement](https://leetcode.com/problems/integer-replacement/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Integer%20Replacement/integer-replacement.js) | | Medium |

| 396 | [Rotate Function](https://leetcode.com/problems/rotate-function/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rotate%20Function/rotate-function.js) | | Medium |

| 395 | [Longest Substring with At Least K Repeating Characters](https://leetcode.com/problems/longest-substring-with-at-least-k-repeating-characters/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Substring%20with%20At%20Least%20K%20Repeating%20Characters/not-a-good-solution.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Substring%20with%20At%20Least%20K%20Repeating%20Characters/readme.md) | Medium |

| 394 | [Decode String](https://leetcode.com/problems/decode-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Decode%20String/decode-string.js) | | Medium |

| 393 | [UTF-8 Validation](https://leetcode.com/problems/utf-8-validation/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/UTF-8%20Validation/utf-8-validation.js) | | Medium |

| 392 | [Is Subsequence](https://leetcode.com/problems/is-subsequence/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Is%20Subsequence/is-subsequence.js) | | Medium |

| 391 | [Perfect Rectangle](https://leetcode.com/problems/perfect-rectangle/) | | | Hard |

| 390 | [Elimination Game](https://leetcode.com/problems/elimination-game/) | | | Medium |

| 389 | [Find the Difference](https://leetcode.com/problems/find-the-difference/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20the%20Difference/find-the-difference.js) | | Easy |

| 388 | [Longest Absolute File Path](https://leetcode.com/problems/longest-absolute-file-path/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Absolute%20File%20Path/longest-absolute-file-path.js) | | Medium |

| 387 | [First Unique Character in a String](https://leetcode.com/problems/first-unique-character-in-a-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/First%20Unique%20Character%20in%20a%20String/first-unique-character-in-a-string.js) | | Easy |

| 386 | [Lexicographical Numbers](https://leetcode.com/problems/lexicographical-numbers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Lexicographical%20Numbers/lexicographical-numbers.js) | | Medium |

| 385 | [Mini Parser](https://leetcode.com/problems/mini-parser/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Mini%20Parser/mini-parser.js) | | Medium |

| 384 | [Shuffle an Array](https://leetcode.com/problems/shuffle-an-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Shuffle%20an%20Array/shuffle-an-array.js) | | Medium |

| 383 | [Ransom Note](https://leetcode.com/problems/ransom-note/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Ransom%20Note/ransom-note.js) | | Easy |

| 382 | [Linked List Random Node](https://leetcode.com/problems/linked-list-random-node/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Linked%20List%20Random%20Node/linked-list-random-node.js) | | Medium |

| 381 | [Insert Delete GetRandom O(1) - Duplicates allowed](https://leetcode.com/problems/insert-delete-getrandom-o1-duplicates-allowed/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Insert%20Delete%20GetRandom%20O(1)%20-%20Duplicates%20allowed/insert-delete-getrandom-o1-duplicates-allowed.py) | | Hard |

| 380 | [Insert Delete GetRandom O(1)](https://leetcode.com/problems/insert-delete-getrandom-o1/) | [Python](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Insert%20Delete%20GetRandom%20O(1)/insert-delete-getrandom-o1.py) | | Medium |

| 379 | [Design Phone Directory](https://leetcode.com/problems/design-phone-directory/) :blue_book: | | | Medium |

| 378 | [Kth Smallest Element in a Sorted Matrix](https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Kth%20Smallest%20Element%20in%20a%20Sorted%20Matrix/kth-smallest-element-in-a-sorted-matrix.js) | | Medium |

| 377 | [Combination Sum IV](https://leetcode.com/problems/combination-sum-iv/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Combination%20Sum%20IV/combination-sum-iv.js) | | Medium |

| 376 | [Wiggle Subsequence](https://leetcode.com/problems/wiggle-subsequence/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Wiggle%20Subsequence/wiggle-subsequence.js) | | Medium |

| 375 | [Guess Number Higher or Lower II](https://leetcode.com/problems/guess-number-higher-or-lower-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Guess%20Number%20Higher%20or%20Lower%20II/guess-number-higher-or-lower-ii.js) | | Medium |

| 374 | [Guess Number Higher or Lower](https://leetcode.com/problems/guess-number-higher-or-lower/) | [C++](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Guess%20Number%20Higher%20or%20Lower/guess-number-higher-or-lower.cpp) | | Easy |

| 373 | [Find K Pairs with Smallest Sums](https://leetcode.com/problems/find-k-pairs-with-smallest-sums/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20K%20Pairs%20with%20Smallest%20Sums/find-k-pairs-with-smallest-sums.js) | | Medium |

| 372 | [Super Pow](https://leetcode.com/problems/super-pow/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Super%20Pow/super-pow.js) | | Medium |

| 371 | [Sum of Two Integers](https://leetcode.com/problems/sum-of-two-integers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sum%20of%20Two%20Integers/sum-of-two-integers.js) | | Easy |

| 370 | [Range Addition](https://leetcode.com/problems/range-addition/) :blue_book: | | | Medium |

| 369 | [Plus One Linked List](https://leetcode.com/problems/plus-one-linked-list/) :blue_book: | | | Medium |

| 368 | [Largest Divisible Subset](https://leetcode.com/problems/largest-divisible-subset/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Largest%20Divisible%20Subset/largest-divisible-subset.js) | | Medium |

| 367 | [Valid Perfect Square](https://leetcode.com/problems/valid-perfect-square/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Perfect%20Square/valid-perfect-square.js) | | Easy |

| 366 | [Find Leaves of Binary Tree](https://leetcode.com/problems/find-leaves-of-binary-tree/) :blue_book: | | | Medium |

| 365 | [Water and Jug Problem](https://leetcode.com/problems/water-and-jug-problem/) | | | Medium |

| 364 | [Nested List Weight Sum II](https://leetcode.com/problems/nested-list-weight-sum-ii/) :blue_book: | | | Medium |

| 363 | [Max Sum of Rectangle No Larger Than K](https://leetcode.com/problems/max-sum-of-rectangle-no-larger-than-k/) | | | Hard |

| 362 | [Design Hit Counter](https://leetcode.com/problems/design-hit-counter/) :blue_book: | | | Medium |

| 361 | [Bomb Enemy](https://leetcode.com/problems/bomb-enemy/) :blue_book: | | | Medium |

| 360 | [Sort Transformed Array](https://leetcode.com/problems/sort-transformed-array/) :blue_book: | | | Medium |

| 359 | [Logger Rate Limiter](https://leetcode.com/problems/logger-rate-limiter/) :blue_book: | | | Easy |

| 358 | [Rearrange String k Distance Apart](https://leetcode.com/problems/rearrange-string-k-distance-apart/) :blue_book: | | | Hard |

| 357 | [Count Numbers with Unique Digits](https://leetcode.com/problems/count-numbers-with-unique-digits/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20Numbers%20with%20Unique%20Digits/count-numbers-with-unique-digits.js) | | Medium |

| 356 | [Line Reflection](https://leetcode.com/problems/line-reflection/) :blue_book: | | | Medium |

| 355 | [Design Twitter](https://leetcode.com/problems/design-twitter/) | | | Medium |

| 354 | [Russian Doll Envelopes](https://leetcode.com/problems/russian-doll-envelopes/) | | | Hard |

| 353 | [Design Snake Game](https://leetcode.com/problems/design-snake-game/) :blue_book: | | | Medium |

| 352 | [Data Stream as Disjoint Intervals](https://leetcode.com/problems/data-stream-as-disjoint-intervals/) | | | Hard |

| 351 | [Android Unlock Patterns](https://leetcode.com/problems/android-unlock-patterns/) :blue_book: | | | Medium |

| 350 | [Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Intersection%20of%20Two%20Arrays%20II/intersection-of-two-arrays-ii.js) | | Easy |

| 349 | [Intersection of Two Arrays](https://leetcode.com/problems/intersection-of-two-arrays/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Intersection%20of%20Two%20Arrays/intersection-of-two-arrays.js) | | Easy |

| 348 | [Design Tic-Tac-Toe](https://leetcode.com/problems/design-tic-tac-toe/) :blue_book: | | | Medium |

| 347 | [Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Top%20K%20Frequent%20Elements/top-k-frequent-elements.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Top%20K%20Frequent%20Elements/README.md) | Medium |

| 346 | [Moving Average from Data Stream](https://leetcode.com/problems/moving-average-from-data-stream/) :blue_book: | | | Easy |

| 345 | [Reverse Vowels of a String](https://leetcode.com/problems/reverse-vowels-of-a-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Vowels%20of%20a%20String/reverse-vowels-of-a-string.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Vowels%20of%20a%20String/README.md) | Easy |

| 344 | [Reverse String](https://leetcode.com/problems/reverse-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20String/reverse-string.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20String/README.md) | Easy |

| 343 | [Integer Break](https://leetcode.com/problems/integer-break/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Integer%20Break/integer-break.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Integer%20Break/README.md) | Medium |

| 342 | [Power of Four](https://leetcode.com/problems/power-of-four/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Power%20of%20Four/power-of-four.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Power%20of%20Four/README.md) | Easy |

| 341 | [Flatten Nested List Iterator](https://leetcode.com/problems/flatten-nested-list-iterator/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Flatten%20Nested%20List%20Iterator/flatten-nested-list-iterator.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Flatten%20Nested%20List%20Iterator/README.md) | Medium |

| 340 | [Longest Substring with At Most K Distinct Characters](https://leetcode.com/problems/longest-substring-with-at-most-k-distinct-characters/) :blue_book: | | | Hard |

| 339 | [Nested List Weight Sum](https://leetcode.com/problems/nested-list-weight-sum/) :blue_book: | | | Easy |

| 338 | [Counting Bits](https://leetcode.com/problems/counting-bits/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Counting%20Bits/counting-bits.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Counting%20Bits/README.md) | Medium |

| 337 | [House Robber III](https://leetcode.com/problems/house-robber-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/House%20Robber%20III/house-robber-iii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/House%20Robber%20III/README.md) | Medium |

| 336 | [Palindrome Pairs](https://leetcode.com/problems/palindrome-pairs/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Pairs/use_object_to_hash.js) | | Hard |

| 335 | [Self Crossing](https://leetcode.com/problems/self-crossing/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Self%20Crossing/self-crossing.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Self%20Crossing/README.md) | Hard |

| 334 | [Increasing Triplet Subsequence](https://leetcode.com/problems/increasing-triplet-subsequence/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Increasing%20Triplet%20Subsequence/increasing-triplet-subsequence.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Increasing%20Triplet%20Subsequence/README.md) | Medium |

| 333 | [Largest BST Subtree](https://leetcode.com/problems/largest-bst-subtree/) :blue_book: | | | Medium |

| 332 | [Reconstruct Itinerary](https://leetcode.com/problems/reconstruct-itinerary/) | | | Medium |

| 331 | [Verify Preorder Serialization of a Binary Tree](https://leetcode.com/problems/verify-preorder-serialization-of-a-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Verify%20Preorder%20Serialization%20of%20a%20Binary%20Tree/verify-preorder-serialization-of-a-binary-tree.js) | | Medium |

| 330 | [Patching Array](https://leetcode.com/problems/patching-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Patching%20Array/patching-array.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Patching%20Array/README.md) | Hard |

| 329 | [Longest Increasing Path in a Matrix](https://leetcode.com/problems/longest-increasing-path-in-a-matrix/) | | | Hard |

| 328 | [Odd Even Linked List](https://leetcode.com/problems/odd-even-linked-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Odd%20Even%20Linked%20List/odd-even-linked-list.js) | | Medium |

| 327 | [Count of Range Sum](https://leetcode.com/problems/count-of-range-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20of%20Range%20Sum/count-of-range-sum.js) | | Hard |

| 326 | [Power of Three](https://leetcode.com/problems/power-of-three/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Power%20of%20Three/power-of-three.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Power%20of%20Three/README.md) | Easy |

| 325 | [Maximum Size Subarray Sum Equals k](https://leetcode.com/problems/maximum-size-subarray-sum-equals-k/) :blue_book: | | | Medium |

| 324 | [Wiggle Sort II](https://leetcode.com/problems/wiggle-sort-ii/) | | | Medium |

| 323 | [Number of Connected Components in an Undirected Graph](https://leetcode.com/problems/number-of-connected-components-in-an-undirected-graph/) :blue_book: | | | Medium |

| 322 | [Coin Change](https://leetcode.com/problems/coin-change/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Coin%20Change/coin-change.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Coin%20Change/README.md) | Medium |

| 321 | [Create Maximum Number](https://leetcode.com/problems/create-maximum-number/) | | | Hard |

| 320 | [Generalized Abbreviation](https://leetcode.com/problems/generalized-abbreviation/) :blue_book: | | | Medium |

| 319 | [Bulb Switcher](https://leetcode.com/problems/bulb-switcher/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Bulb%20Switcher/bulb-switcher.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Bulb%20Switcher/README.md) | Medium |

| 318 | [Maximum Product of Word Lengths](https://leetcode.com/problems/maximum-product-of-word-lengths/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20Product%20of%20Word%20Lengths/maximum-product-of-word-lengths.js) | | Medium |

| 317 | [Shortest Distance from All Buildings](https://leetcode.com/problems/shortest-distance-from-all-buildings/) :blue_book: | | | Hard |

| 316 | [Remove Duplicate Letters](https://leetcode.com/problems/remove-duplicate-letters/) | | | Hard |

| 315 | [Count of Smaller Numbers After Self](https://leetcode.com/problems/count-of-smaller-numbers-after-self/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20of%20Smaller%20Numbers%20After%20Self/BinarySearch.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20of%20Smaller%20Numbers%20After%20Self/README.md) | Hard |

| 314 | [Binary Tree Vertical Order Traversal](https://leetcode.com/problems/binary-tree-vertical-order-traversal/) :blue_book: | | | Medium |

| 313 | [Super Ugly Number](https://leetcode.com/problems/super-ugly-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Super%20Ugly%20Number/super-ugly-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Super%20Ugly%20Number/README.md) | Medium |

| 312 | [Burst Balloons](https://leetcode.com/problems/burst-balloons/) | | | Hard |

| 311 | [Sparse Matrix Multiplication](https://leetcode.com/problems/sparse-matrix-multiplication/) :blue_book: | | | Medium |

| 310 | [Minimum Height Trees](https://leetcode.com/problems/minimum-height-trees/) | | | Medium |

| 309 | [Best Time to Buy and Sell Stock with Cooldown](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-with-cooldown/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20with%20Cooldown/best-time-to-buy-and-sell-stock-with-cooldown.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20with%20Cooldown/README.md) | Medium |

| 308 | [Range Sum Query 2D - Mutable](https://leetcode.com/problems/range-sum-query-2d-mutable/) :blue_book: | | | Hard |

| 307 | [Range Sum Query - Mutable](https://leetcode.com/problems/range-sum-query-mutable/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Range%20Sum%20Query%20-%20Mutable/range-sum-query-mutable.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Range%20Sum%20Query%20-%20Mutable/README.md) | Medium |

| 306 | [Additive Number](https://leetcode.com/problems/additive-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Additive%20Number/additive-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Additive%20Number/README.md) | Medium |

| 305 | [Number of Islands II](https://leetcode.com/problems/number-of-islands-ii/) :blue_book: | | | Hard |

| 304 | [Range Sum Query 2D - Immutable](https://leetcode.com/problems/range-sum-query-2d-immutable/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Range%20Sum%20Query%202D%20-%20Immutable/range-sum-query-2d-immutable.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Range%20Sum%20Query%202D%20-%20Immutable/README.md) | Medium |

| 303 | [Range Sum Query - Immutable](https://leetcode.com/problems/range-sum-query-immutable/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Range%20Sum%20Query%20-%20Immutable/range-sum-query-immutable.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Range%20Sum%20Query%20-%20Immutable/README.md) | Easy |

| 302 | [Smallest Rectangle Enclosing Black Pixels](https://leetcode.com/problems/smallest-rectangle-enclosing-black-pixels/) :blue_book: | | | Hard |

| 301 | [Remove Invalid Parentheses](https://leetcode.com/problems/remove-invalid-parentheses/) | | | Hard |

| 300 | [Longest Increasing Subsequence](https://leetcode.com/problems/longest-increasing-subsequence/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Increasing%20Subsequence/longest-increasing-subsequence.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Increasing%20Subsequence/README.md) | Medium |

| 299 | [Bulls and Cows](https://leetcode.com/problems/bulls-and-cows/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Bulls%20and%20Cows/bulls-and-cows.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Bulls%20and%20Cows/README.md) | Medium |

| 298 | [Binary Tree Longest Consecutive Sequence](https://leetcode.com/problems/binary-tree-longest-consecutive-sequence/) :blue_book: | | | Medium |

| 297 | [Serialize and Deserialize Binary Tree](https://leetcode.com/problems/serialize-and-deserialize-binary-tree/) | | | Hard |

| 296 | [Best Meeting Point](https://leetcode.com/problems/best-meeting-point/) :blue_book: | | | Hard |

| 295 | [Find Median from Data Stream](https://leetcode.com/problems/find-median-from-data-stream/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Median%20from%20Data%20Stream/find-median-from-data-stream.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Median%20from%20Data%20Stream/README.md) | Hard |

| 294 | [Flip Game II](https://leetcode.com/problems/flip-game-ii/) :blue_book: | | | Medium |

| 293 | [Flip Game](https://leetcode.com/problems/flip-game/) :blue_book: | | | Easy |

| 292 | [Nim Game](https://leetcode.com/problems/nim-game/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Nim%20Game/nim-game.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Nim%20Game/README.md) | Easy |

| 291 | [Word Pattern II](https://leetcode.com/problems/word-pattern-ii/) :blue_book: | | | Hard |

| 290 | [Word Pattern](https://leetcode.com/problems/word-pattern/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Word%20Pattern/word-pattern.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Word%20Pattern/README.md) | Easy |

| 289 | [Game of Life](https://leetcode.com/problems/game-of-life/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Game%20of%20Life/game-of-life.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Game%20of%20Life/README.md) | Medium |

| 288 | [Unique Word Abbreviation](https://leetcode.com/problems/unique-word-abbreviation/) :blue_book: | | | Medium |

| 287 | [Find the Duplicate Number](https://leetcode.com/problems/find-the-duplicate-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20the%20Duplicate%20Number/find-the-duplicate-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20the%20Duplicate%20Number/README.md) | Medium |

| 286 | [Walls and Gates](https://leetcode.com/problems/walls-and-gates/) :blue_book: | | | Medium |

| 285 | [Inorder Successor in BST](https://leetcode.com/problems/inorder-successor-in-bst/) :blue_book: | | | Medium |

| 284 | [Peeking Iterator](https://leetcode.com/problems/peeking-iterator/) | | | Medium |

| 283 | [Move Zeroes](https://leetcode.com/problems/move-zeroes/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Move%20Zeroes/move-zeroes.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Move%20Zeroes/README.md) | Easy |

| 282 | [Expression Add Operators](https://leetcode.com/problems/expression-add-operators/) | | | Hard |

| 281 | [Zigzag Iterator](https://leetcode.com/problems/zigzag-iterator/) :blue_book: | | | Medium |

| 280 | [Wiggle Sort](https://leetcode.com/problems/wiggle-sort/) :blue_book: | | | Medium |

| 279 | [Perfect Squares](https://leetcode.com/problems/perfect-squares/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Perfect%20Squares/perfect-squares.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Perfect%20Squares/README.md) | Medium |

| 278 | [First Bad Version](https://leetcode.com/problems/first-bad-version/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/First%20Bad%20Version/first-bad-version.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/First%20Bad%20Version/README.md) | Easy |

| 277 | [Find the Celebrity](https://leetcode.com/problems/find-the-celebrity/) :blue_book: | | | Medium |

| 276 | [Paint Fence](https://leetcode.com/problems/paint-fence/) :blue_book: | | | Easy |

| 275 | [H-Index II](https://leetcode.com/problems/h-index-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/H-Index%20II/h-index-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/H-Index%20II/README.md) | Medium |

| 274 | [H-Index](https://leetcode.com/problems/h-index/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/H-Index/h-index.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/H-Index/README.md) | Medium |

| 273 | [Integer to English Words](https://leetcode.com/problems/integer-to-english-words/) | | | Hard |

| 272 | [Closest Binary Search Tree Value II](https://leetcode.com/problems/closest-binary-search-tree-value-ii/) :blue_book: | | | Hard |

| 271 | [Encode and Decode Strings](https://leetcode.com/problems/encode-and-decode-strings/) :blue_book: | | | Medium |

| 270 | [Closest Binary Search Tree Value](https://leetcode.com/problems/closest-binary-search-tree-value/) :blue_book: | | | Easy |

| 269 | [Alien Dictionary](https://leetcode.com/problems/alien-dictionary/) :blue_book: | | | Hard |

| 268 | [Missing Number](https://leetcode.com/problems/missing-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Missing%20Number/missing-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Missing%20Number/README.md) | Easy |

| 267 | [Palindrome Permutation II](https://leetcode.com/problems/palindrome-permutation-ii/) :blue_book: | | | Medium |

| 266 | [Palindrome Permutation](https://leetcode.com/problems/palindrome-permutation/) :blue_book: | | | Easy |

| 265 | [Paint House II](https://leetcode.com/problems/paint-house-ii/) :blue_book: | | | Hard |

| 264 | [Ugly Number II](https://leetcode.com/problems/ugly-number-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Ugly%20Number%20II/ugly-number-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Ugly%20Number%20II/README.md) | Medium |

| 263 | [Ugly Number](https://leetcode.com/problems/ugly-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Ugly%20Number/ugly-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Ugly%20Number/README.md) | Easy |

| 261 | [Graph Valid Tree](https://leetcode.com/problems/graph-valid-tree/) :blue_book: | | | Medium |

| 260 | [Single Number III](https://leetcode.com/problems/single-number-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Single%20Number%20III/single-number-iii.js) | | Medium |

| 259 | [3Sum Smaller](https://leetcode.com/problems/3sum-smaller/) :blue_book: | | | Medium |

| 258 | [Add Digits](https://leetcode.com/problems/add-digits/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Digits/add-digits.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Digits/README.md) | Easy |

| 257 | [Binary Tree Paths](https://leetcode.com/problems/binary-tree-paths/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Paths/binary-tree-paths.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Paths/README.md) | Easy |

| 256 | [Paint House](https://leetcode.com/problems/paint-house/) :blue_book: | | | Easy |

| 255 | [Verify Preorder Sequence in Binary Search Tree](https://leetcode.com/problems/verify-preorder-sequence-in-binary-search-tree/) :blue_book: | | | Medium |

| 254 | [Factor Combinations](https://leetcode.com/problems/factor-combinations/) :blue_book: | | | Medium |

| 253 | [Meeting Rooms II](https://leetcode.com/problems/meeting-rooms-ii/) :blue_book: | | | Medium |

| 252 | [Meeting Rooms](https://leetcode.com/problems/meeting-rooms/) :blue_book: | | | Easy |

| 251 | [Flatten 2D Vector](https://leetcode.com/problems/flatten-2d-vector/) :blue_book: | | | Medium |

| 250 | [Count Univalue Subtrees](https://leetcode.com/problems/count-univalue-subtrees/) :blue_book: | | | Medium |

| 249 | [Group Shifted Strings](https://leetcode.com/problems/group-shifted-strings/) :blue_book: | | | Medium |

| 248 | [Strobogrammatic Number III](https://leetcode.com/problems/strobogrammatic-number-iii/) :blue_book: | | | Hard |

| 247 | [Strobogrammatic Number II](https://leetcode.com/problems/strobogrammatic-number-ii/) :blue_book: | | | Medium |

| 246 | [Strobogrammatic Number](https://leetcode.com/problems/strobogrammatic-number/) :blue_book: | | | Easy |

| 245 | [Shortest Word Distance III](https://leetcode.com/problems/shortest-word-distance-iii/) :blue_book: | | | Medium |

| 244 | [Shortest Word Distance II](https://leetcode.com/problems/shortest-word-distance-ii/) :blue_book: | | | Medium |

| 243 | [Shortest Word Distance](https://leetcode.com/problems/shortest-word-distance/) :blue_book: | | | Easy |

| 242 | [Valid Anagram](https://leetcode.com/problems/valid-anagram/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Anagram/valid-anagram.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Anagram/README.md) | Easy |

| 241 | [Different Ways to Add Parentheses](https://leetcode.com/problems/different-ways-to-add-parentheses/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Different%20Ways%20to%20Add%20Parentheses/divide-and-conquer.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Different%20Ways%20to%20Add%20Parentheses/README.md) | Medium |

| 240 | [Search a 2D Matrix II](https://leetcode.com/problems/search-a-2d-matrix-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20a%202D%20Matrix%20II/search-a-2d-matrix-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20a%202D%20Matrix%20II/README.md) | Medium |

| 239 | [Sliding Window Maximum](https://leetcode.com/problems/sliding-window-maximum/) | | | Hard |

| 238 | [Product of Array Except Self](https://leetcode.com/problems/product-of-array-except-self/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Product%20of%20Array%20Except%20Self/product-of-array-except-self.js) | | Medium |

| 237 | [Delete Node in a Linked List](https://leetcode.com/problems/delete-node-in-a-linked-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Delete%20Node%20in%20a%20Linked%20List/delete-node-in-a-linked-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Delete%20Node%20in%20a%20Linked%20List/README.md) | Easy |

| 236 | [Lowest Common Ancestor of a Binary Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Lowest%20Common%20Ancestor%20of%20a%20Binary%20Tree/lowest-common-ancestor-of-a-binary-tree.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Lowest%20Common%20Ancestor%20of%20a%20Binary%20Tree/readme.md) | Medium |

| 235 | [Lowest Common Ancestor of a Binary Search Tree](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Lowest%20Common%20Ancestor%20of%20a%20Binary%20Search%20Tree/lowest-common-ancestor-of-a-binary-search-tree.js) | | Easy |

| 234 | [Palindrome Linked List](https://leetcode.com/problems/palindrome-linked-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Linked%20List/palindrome-linked-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Linked%20List/README.md) | Easy |

| 233 | [Number of Digit One](https://leetcode.com/problems/number-of-digit-one/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20of%20Digit%20One/number-of-digit-one.js) | | Hard |

| 232 | [Implement Queue using Stacks](https://leetcode.com/problems/implement-queue-using-stacks/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20Queue%20using%20Stacks/implement-queue-using-stacks.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20Queue%20using%20Stacks/README.md) | Easy |

| 231 | [Power of Two](https://leetcode.com/problems/power-of-two/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Power%20of%20Two/power-of-two.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Power%20of%20Two/README.md) | Easy |

| 230 | [Kth Smallest Element in a BST](https://leetcode.com/problems/kth-smallest-element-in-a-bst/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Kth%20Smallest%20Element%20in%20a%20BST/kth-smallest-element-in-a-bst.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Kth%20Smallest%20Element%20in%20a%20BST/readme.md) | Medium |

| 229 | [Majority Element II](https://leetcode.com/problems/majority-element-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Majority%20Element%20II/majority-element-ii.js) | | Medium |

| 228 | [Summary Ranges](https://leetcode.com/problems/summary-ranges/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Summary%20Ranges/summary-ranges.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Summary%20Ranges/README.md) | Medium |

| 227 | [Basic Calculator II](https://leetcode.com/problems/basic-calculator-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Basic%20Calculator%20II/basic-calculator-ii.js) | | Medium |

| 226 | [Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Invert%20Binary%20Tree/invert-binary-tree.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Invert%20Binary%20Tree/README.md) | Easy |

| 225 | [Implement Stack using Queues](https://leetcode.com/problems/implement-stack-using-queues/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20Stack%20using%20Queues/implement-stack-using-queues.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20Stack%20using%20Queues/README.md) | Easy |

| 224 | [Basic Calculator](https://leetcode.com/problems/basic-calculator/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Basic%20Calculator/better-solution.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Basic%20Calculator/README.md) | Hard |

| 223 | [Rectangle Area](https://leetcode.com/problems/rectangle-area/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rectangle%20Area/index_without_sort.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rectangle%20Area/README.md) | Medium |

| 222 | [Count Complete Tree Nodes](https://leetcode.com/problems/count-complete-tree-nodes/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20Complete%20Tree%20Nodes/binary-search.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20Complete%20Tree%20Nodes/readme.md) | Medium |

| 221 | [Maximal Square](https://leetcode.com/problems/maximal-square/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximal%20Square/index_2.js) | | Medium |

| 220 | [Contains Duplicate III](https://leetcode.com/problems/contains-duplicate-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Contains%20Duplicate%20III/contains-duplicate-iii.js) | | Medium |

| 219 | [Contains Duplicate II](https://leetcode.com/problems/contains-duplicate-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Contains%20Duplicate%20II/contains-duplicate-ii.js) | | Easy |

| 218 | [The Skyline Problem](https://leetcode.com/problems/the-skyline-problem/) | | | Hard |

| 217 | [Contains Duplicate](https://leetcode.com/problems/contains-duplicate/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Contains%20Duplicate/contains-duplicate.js) | | Easy |

| 216 | [Combination Sum III](https://leetcode.com/problems/combination-sum-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Combination%20Sum%20III/combination-sum-iii.js) | | Medium |

| 215 | [Kth Largest Element in an Array](https://leetcode.com/problems/kth-largest-element-in-an-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Kth%20Largest%20Element%20in%20an%20Array/kth-largest-element-in-an-array.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Kth%20Largest%20Element%20in%20an%20Array/README.md) | Medium |

| 214 | [Shortest Palindrome](https://leetcode.com/problems/shortest-palindrome/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Shortest%20Palindrome/shortest-palindrome.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Shortest%20Palindrome/README.md) | Hard |

| 213 | [House Robber II](https://leetcode.com/problems/house-robber-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/House%20Robber%20II/house-robber-ii.js) | | Medium |

| 212 | [Word Search II](https://leetcode.com/problems/word-search-ii/) | | | Hard |

| 211 | [Add and Search Word - Data structure design](https://leetcode.com/problems/add-and-search-word-data-structure-design/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20and%20Search%20Word%20-%20Data%20structure%20design/add-and-search-word-data-structure-design.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20and%20Search%20Word%20-%20Data%20structure%20design/README.md) | Medium |

| 210 | [Course Schedule II](https://leetcode.com/problems/course-schedule-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Course%20Schedule%20II/course-schedule-ii.js) | | Medium |

| 209 | [Minimum Size Subarray Sum](https://leetcode.com/problems/minimum-size-subarray-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Size%20Subarray%20Sum/minimum-size-subarray-sum.js) | | Medium |

| 208 | [Implement Trie (Prefix Tree)](https://leetcode.com/problems/implement-trie-prefix-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20Trie%20(Prefix%20Tree)/implement-trie-prefix-tree.js) | | Medium |

| 207 | [Course Schedule](https://leetcode.com/problems/course-schedule/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Course%20Schedule/course-schedule.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Course%20Schedule/README.md) | Medium |

| 206 | [Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Linked%20List/index%E2%85%A2.js) | | Easy |

| 205 | [Isomorphic Strings](https://leetcode.com/problems/isomorphic-strings/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Isomorphic%20Strings/isomorphic-strings.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Isomorphic%20Strings/README.md) | Easy |

| 204 | [Count Primes](https://leetcode.com/problems/count-primes/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20Primes/count-primes.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20Primes/README.md) | Easy |

| 203 | [Remove Linked List Elements](https://leetcode.com/problems/remove-linked-list-elements/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Linked%20List%20Elements/remove-linked-list-elements.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Linked%20List%20Elements/README.md) | Easy |

| 202 | [Happy Number](https://leetcode.com/problems/happy-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Happy%20Number/happy-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Happy%20Number/README.md) | Easy |

| 201 | [Bitwise AND of Numbers Range](https://leetcode.com/problems/bitwise-and-of-numbers-range/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Bitwise%20AND%20of%20Numbers%20Range/bitwise-and-of-numbers-range.js) | | Medium |

| 200 | [Number of Islands](https://leetcode.com/problems/number-of-islands/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20of%20Islands/number-of-islands.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20of%20Islands/README.md) | Medium |

| 199 | [Binary Tree Right Side View](https://leetcode.com/problems/binary-tree-right-side-view/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Right%20Side%20View/binary-tree-right-side-view.js) | | Medium |

| 198 | [House Robber](https://leetcode.com/problems/house-robber/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/House%20Robber/house-robber.js) | | Easy |

| 191 | [Number of 1 Bits](https://leetcode.com/problems/number-of-1-bits/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Number%20of%201%20Bits/number-of-1-bits.js) | | Easy |

| 190 | [Reverse Bits](https://leetcode.com/problems/reverse-bits/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Bits/reverse-bits.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Bits/README.md) | Easy |

| 189 | [Rotate Array](https://leetcode.com/problems/rotate-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rotate%20Array/rotate-array.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rotate%20Array/README.md) | Easy |

| 188 | [Best Time to Buy and Sell Stock IV](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/) | | | Hard |

| 187 | [Repeated DNA Sequences](https://leetcode.com/problems/repeated-dna-sequences/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Repeated%20DNA%20Sequences/repeated-dna-sequences.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Repeated%20DNA%20Sequences/README.md) | Medium |

| 186 | [Reverse Words in a String II](https://leetcode.com/problems/reverse-words-in-a-string-ii/) :blue_book: | | | Medium |

| 179 | [Largest Number](https://leetcode.com/problems/largest-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Largest%20Number/largest-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Largest%20Number/README.md) | Medium |

| 174 | [Dungeon Game](https://leetcode.com/problems/dungeon-game/) | | | Hard |

| 173 | [Binary Search Tree Iterator](https://leetcode.com/problems/binary-search-tree-iterator/) | | | Medium |

| 172 | [Factorial Trailing Zeroes](https://leetcode.com/problems/factorial-trailing-zeroes/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Factorial%20Trailing%20Zeroes/factorial-trailing-zeroes.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Factorial%20Trailing%20Zeroes/README.md) | Easy |

| 171 | [Excel Sheet Column Number](https://leetcode.com/problems/excel-sheet-column-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Excel%20Sheet%20Column%20Number/excel-sheet-column-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Excel%20Sheet%20Column%20Number/README.md) | Easy |

| 170 | [Two Sum III - Data structure design](https://leetcode.com/problems/two-sum-iii-data-structure-design/) :blue_book: | | | Easy |

| 169 | [Majority Element](https://leetcode.com/problems/majority-element/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Majority%20Element/majority-element.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Majority%20Element/README.md) | Easy |

| 168 | [Excel Sheet Column Title](https://leetcode.com/problems/excel-sheet-column-title/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Excel%20Sheet%20Column%20Title/excel-sheet-column-title.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Excel%20Sheet%20Column%20Title/README.md) | Easy |

| 167 | [Two Sum II - Input array is sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Two%20Sum%20II%20-%20Input%20array%20is%20sorted/two-sum-ii-input-array-is-sorted.js) | | Easy |

| 166 | [Fraction to Recurring Decimal](https://leetcode.com/problems/fraction-to-recurring-decimal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Fraction%20to%20Recurring%20Decimal/fraction-to-recurring-decimal.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Fraction%20to%20Recurring%20Decimal/README.md) | Medium |

| 165 | [Compare Version Numbers](https://leetcode.com/problems/compare-version-numbers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Compare%20Version%20Numbers/compare-version-numbers.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Compare%20Version%20Numbers/README.md) | Medium |

| 164 | [Maximum Gap](https://leetcode.com/problems/maximum-gap/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20Gap/maximum-gap.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20Gap/README.md) | Hard |

| 163 | [Missing Ranges](https://leetcode.com/problems/missing-ranges/) :blue_book: | | | Medium |

| 162 | [Find Peak Element](https://leetcode.com/problems/find-peak-element/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Peak%20Element/find-peak-element.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Peak%20Element/README.md) | Medium |

| 161 | [One Edit Distance](https://leetcode.com/problems/one-edit-distance/) :blue_book: | | | Medium |

| 160 | [Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Intersection%20of%20Two%20Linked%20Lists/intersection-of-two-linked-lists.js) | | Easy |

| 159 | [Longest Substring with At Most Two Distinct Characters](https://leetcode.com/problems/longest-substring-with-at-most-two-distinct-characters/) :blue_book: | | | Hard |

| 158 | [Read N Characters Given Read4 II - Call multiple times](https://leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/) :blue_book: | | | Hard |

| 157 | [Read N Characters Given Read4](https://leetcode.com/problems/read-n-characters-given-read4/) :blue_book: | | | Easy |

| 156 | [Binary Tree Upside Down](https://leetcode.com/problems/binary-tree-upside-down/) :blue_book: | | | Medium |

| 155 | [Min Stack](https://leetcode.com/problems/min-stack/) | | | Easy |

| 154 | [Find Minimum in Rotated Sorted Array II](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Minimum%20in%20Rotated%20Sorted%20Array%20II/find-minimum-in-rotated-sorted-array-ii.js) | | Hard |

| 153 | [Find Minimum in Rotated Sorted Array](https://leetcode.com/problems/find-minimum-in-rotated-sorted-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Find%20Minimum%20in%20Rotated%20Sorted%20Array/find-minimum-in-rotated-sorted-array.js) | | Medium |

| 152 | [Maximum Product Subarray](https://leetcode.com/problems/maximum-product-subarray/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20Product%20Subarray/maximum-product-subarray.js) | | Medium |

| 151 | [Reverse Words in a String](https://leetcode.com/problems/reverse-words-in-a-string/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Words%20in%20a%20String/reverse-words-in-a-string.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Words%20in%20a%20String/README.md) | Medium |

| 150 | [Evaluate Reverse Polish Notation](https://leetcode.com/problems/evaluate-reverse-polish-notation/) | | | Medium |

| 149 | [Max Points on a Line](https://leetcode.com/problems/max-points-on-a-line/) | | | Hard |

| 148 | [Sort List](https://leetcode.com/problems/sort-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sort%20List/sort-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sort%20List/README.md) | Medium |

| 147 | [Insertion Sort List](https://leetcode.com/problems/insertion-sort-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Insertion%20Sort%20List/insertion-sort-list.js) | | Medium |

| 146 | [LRU Cache](https://leetcode.com/problems/lru-cache/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/LRU%20Cache/lru-cache.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/LRU%20Cache/README.md) | Hard |

| 145 | [Binary Tree Postorder Traversal](https://leetcode.com/problems/binary-tree-postorder-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Postorder%20Traversal/binary-tree-postorder-traversal.js) | | Hard |

| 144 | [Binary Tree Preorder Traversal](https://leetcode.com/problems/binary-tree-preorder-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Preorder%20Traversal/binary-tree-preorder-traversal.js) | | Medium |

| 143 | [Reorder List](https://leetcode.com/problems/reorder-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reorder%20List/reorder-list.js) | | Medium |

| 142 | [Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Linked%20List%20Cycle%20II/linked-list-cycle-ii.js) | | Medium |

| 141 | [Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Linked%20List%20Cycle/linked-list-cycle.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Linked%20List%20Cycle/README.md) | Easy |

| 140 | [Word Break II](https://leetcode.com/problems/word-break-ii/) | | | Hard |

| 139 | [Word Break](https://leetcode.com/problems/word-break/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Word%20Break/word-break.js) | | Medium |

| 138 | [Copy List with Random Pointer](https://leetcode.com/problems/copy-list-with-random-pointer/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Copy%20List%20with%20Random%20Pointer/copy-list-with-random-pointer.js) | | Medium |

| 137 | [Single Number II](https://leetcode.com/problems/single-number-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Single%20Number%20II/single-number-ii.js) | | Medium |

| 136 | [Single Number](https://leetcode.com/problems/single-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Single%20Number/single-number.js) | | Easy |

| 135 | [Candy](https://leetcode.com/problems/candy/) | | | Hard |

| 134 | [Gas Station](https://leetcode.com/problems/gas-station/) | | | Medium |

| 133 | [Clone Graph](https://leetcode.com/problems/clone-graph/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Clone%20Graph/clone-graph.js) | | Medium |

| 132 | [Palindrome Partitioning II](https://leetcode.com/problems/palindrome-partitioning-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Partitioning%20II/palindrome-partitioning-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Partitioning%20II/README.md) | Hard |

| 131 | [Palindrome Partitioning](https://leetcode.com/problems/palindrome-partitioning/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Partitioning/palindrome-partitioning.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Partitioning/README.md) | Medium |

| 130 | [Surrounded Regions](https://leetcode.com/problems/surrounded-regions/) | | | Medium |

| 129 | [Sum Root to Leaf Numbers](https://leetcode.com/problems/sum-root-to-leaf-numbers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sum%20Root%20to%20Leaf%20Numbers/sum-root-to-leaf-numbers.js) | | Medium |

| 128 | [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Consecutive%20Sequence/longest-consecutive-sequence.js) | | Hard |

| 127 | [Word Ladder](https://leetcode.com/problems/word-ladder/) | | | Medium |

| 126 | [Word Ladder II](https://leetcode.com/problems/word-ladder-ii/) | | | Hard |

| 125 | [Valid Palindrome](https://leetcode.com/problems/valid-palindrome/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Palindrome/valid-palindrome.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Palindrome/README.md) | Easy |

| 124 | [Binary Tree Maximum Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/) | | | Hard |

| 123 | [Best Time to Buy and Sell Stock III](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20III/best-time-to-buy-and-sell-stock-iii.js) | | Hard |

| 122 | [Best Time to Buy and Sell Stock II](https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20II/dp_solution.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20II/README.md) | Easy |

| 121 | [Best Time to Buy and Sell Stock](https://leetcode.com/problems/best-time-to-buy-and-sell-stock/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock/best-time-to-buy-and-sell-stock.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Best%20Time%20to%20Buy%20and%20Sell%20Stock/README.md) | Easy |

| 120 | [Triangle](https://leetcode.com/problems/triangle/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Triangle/triangle.js) | | Medium |

| 119 | [Pascal's Triangle II](https://leetcode.com/problems/pascals-triangle-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pascal's%20Triangle%20II/pascals-triangle-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pascal's%20Triangle%20II/README.md) | Easy |

| 118 | [Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pascal's%20Triangle/pascals-triangle.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pascal's%20Triangle/README.md) | Easy |

| 117 | [Populating Next Right Pointers in Each Node II](https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Populating%20Next%20Right%20Pointers%20in%20Each%20Node%20II/bfs-solution.js) | | Medium |

| 116 | [Populating Next Right Pointers in Each Node](https://leetcode.com/problems/populating-next-right-pointers-in-each-node/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Populating%20Next%20Right%20Pointers%20in%20Each%20Node/dfs-solution.js) | | Medium |

| 115 | [Distinct Subsequences](https://leetcode.com/problems/distinct-subsequences/) | | | Hard |

| 114 | [Flatten Binary Tree to Linked List](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Flatten%20Binary%20Tree%20to%20Linked%20List/flatten-binary-tree-to-linked-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Flatten%20Binary%20Tree%20to%20Linked%20List/README.md) | Medium |

| 113 | [Path Sum II](https://leetcode.com/problems/path-sum-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Path%20Sum%20II/path-sum-ii.js) | | Medium |

| 112 | [Path Sum](https://leetcode.com/problems/path-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Path%20Sum/path-sum.js) | | Easy |

| 111 | [Minimum Depth of Binary Tree](https://leetcode.com/problems/minimum-depth-of-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Depth%20of%20Binary%20Tree/minimum-depth-of-binary-tree.js) | | Easy |

| 110 | [Balanced Binary Tree](https://leetcode.com/problems/balanced-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Balanced%20Binary%20Tree/balanced-binary-tree.js) | | Easy |

| 109 | [Convert Sorted List to Binary Search Tree](https://leetcode.com/problems/convert-sorted-list-to-binary-search-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Convert%20Sorted%20List%20to%20Binary%20Search%20Tree/convert-sorted-list-to-binary-search-tree.js) | | Medium |

| 108 | [Convert Sorted Array to Binary Search Tree](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Convert%20Sorted%20Array%20to%20Binary%20Search%20Tree/convert-sorted-array-to-binary-search-tree.js) | | Easy |

| 107 | [Binary Tree Level Order Traversal II](https://leetcode.com/problems/binary-tree-level-order-traversal-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Level%20Order%20Traversal%20II/binary-tree-level-order-traversal-ii.js) | | Easy |

| 106 | [Construct Binary Tree from Inorder and Postorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Construct%20Binary%20Tree%20from%20Inorder%20and%20Postorder%20Traversal/construct-binary-tree-from-inorder-and-postorder-traversal.js) | | Medium |

| 105 | [Construct Binary Tree from Preorder and Inorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Construct%20Binary%20Tree%20from%20Preorder%20and%20Inorder%20Traversal/construct-binary-tree-from-preorder-and-inorder-traversal.js) | | Medium |

| 104 | [Maximum Depth of Binary Tree](https://leetcode.com/problems/maximum-depth-of-binary-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20Depth%20of%20Binary%20Tree/maximum-depth-of-binary-tree.js) | | Easy |

| 103 | [Binary Tree Zigzag Level Order Traversal](https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Zigzag%20Level%20Order%20Traversal/binary-tree-zigzag-level-order-traversal.js) | | Medium |

| 102 | [Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Level%20Order%20Traversal/binary-tree-level-order-traversal.js) | | Medium |

| 101 | [Symmetric Tree](https://leetcode.com/problems/symmetric-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Symmetric%20Tree/stupid-solution.js) | | Easy |

| 100 | [Same Tree](https://leetcode.com/problems/same-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Same%20Tree/index%E2%85%A1.js) | | Easy |

| 99 | [Recover Binary Search Tree](https://leetcode.com/problems/recover-binary-search-tree/) | | | Hard |

| 98 | [Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Validate%20Binary%20Search%20Tree/validate-binary-search-tree.js) | | Medium |

| 97 | [Interleaving String](https://leetcode.com/problems/interleaving-string/) | | | Hard |

| 96 | [Unique Binary Search Trees](https://leetcode.com/problems/unique-binary-search-trees/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Unique%20Binary%20Search%20Trees/unique-binary-search-trees.js) | | Medium |

| 95 | [Unique Binary Search Trees II](https://leetcode.com/problems/unique-binary-search-trees-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Unique%20Binary%20Search%20Trees%20II/unique-binary-search-trees-ii.js) | | Medium |

| 94 | [Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Binary%20Tree%20Inorder%20Traversal/binary-tree-inorder-traversal.js) | | Medium |

| 93 | [Restore IP Addresses](https://leetcode.com/problems/restore-ip-addresses/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Restore%20IP%20Addresses/restore-ip-addresses.js) | | Medium |

| 92 | [Reverse Linked List II](https://leetcode.com/problems/reverse-linked-list-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Linked%20List%20II/reverse-linked-list-ii.js) | | Medium |

| 91 | [Decode Ways](https://leetcode.com/problems/decode-ways/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Decode%20Ways/decode-ways.js) | | Medium |

| 90 | [Subsets II](https://leetcode.com/problems/subsets-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Subsets%20II/subsets-ii.js) | | Medium |

| 89 | [Gray Code](https://leetcode.com/problems/gray-code/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Gray%20Code/index%E2%85%A1.js) | | Medium |

| 88 | [Merge Sorted Array](https://leetcode.com/problems/merge-sorted-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Merge%20Sorted%20Array/merge-sorted-array.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Merge%20Sorted%20Array/README.md) | Easy |

| 87 | [Scramble String](https://leetcode.com/problems/scramble-string/) | | | Hard |

| 86 | [Partition List](https://leetcode.com/problems/partition-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Partition%20List/partition-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Partition%20List/README.md) | Medium |

| 85 | [Maximal Rectangle](https://leetcode.com/problems/maximal-rectangle/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximal%20Rectangle/maximal-rectangle.js) | | Hard |

| 84 | [Largest Rectangle in Histogram](https://leetcode.com/problems/largest-rectangle-in-histogram/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Largest%20Rectangle%20in%20Histogram/largest-rectangle-in-histogram.js) | | Hard |

| 83 | [Remove Duplicates from Sorted List](https://leetcode.com/problems/remove-duplicates-from-sorted-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Duplicates%20from%20Sorted%20List/remove-duplicates-from-sorted-list.js) | | Easy |

| 82 | [Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Duplicates%20from%20Sorted%20List%20II/remove-duplicates-from-sorted-list-ii.js) | | Medium |

| 81 | [Search in Rotated Sorted Array II](https://leetcode.com/problems/search-in-rotated-sorted-array-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20in%20Rotated%20Sorted%20Array%20II/search-in-rotated-sorted-array-ii.js) | | Medium |

| 80 | [Remove Duplicates from Sorted Array II](https://leetcode.com/problems/remove-duplicates-from-sorted-array-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Duplicates%20from%20Sorted%20Array%20II/remove-duplicates-from-sorted-array-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Duplicates%20from%20Sorted%20Array%20II/README.md) | Medium |

| 79 | [Word Search](https://leetcode.com/problems/word-search/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Word%20Search/word-search.js) | | Medium |

| 78 | [Subsets](https://leetcode.com/problems/subsets/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Subsets/subsets.js) | | Medium |

| 77 | [Combinations](https://leetcode.com/problems/combinations/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Combinations/combinations.js) | | Medium |

| 76 | [Minimum Window Substring](https://leetcode.com/problems/minimum-window-substring/) | | | Hard |

| 75 | [Sort Colors](https://leetcode.com/problems/sort-colors/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sort%20Colors/sort-colors.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sort%20Colors/README.md) | Medium |

| 74 | [Search a 2D Matrix](https://leetcode.com/problems/search-a-2d-matrix/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20a%202D%20Matrix/search-a-2d-matrix.js) | | Medium |

| 73 | [Set Matrix Zeroes](https://leetcode.com/problems/set-matrix-zeroes/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Set%20Matrix%20Zeroes/set-matrix-zeroes.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Set%20Matrix%20Zeroes/README.md) | Medium |

| 72 | [Edit Distance](https://leetcode.com/problems/edit-distance/) | | | Hard |

| 71 | [Simplify Path](https://leetcode.com/problems/simplify-path/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Simplify%20Path/simplify-path.js) | | Medium |

| 70 | [Climbing Stairs](https://leetcode.com/problems/climbing-stairs/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Climbing%20Stairs/climbing-stairs.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Climbing%20Stairs/README.md) | Easy |

| 69 | [Sqrt(x)](https://leetcode.com/problems/sqrtx/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sqrt(x)/sqrtx.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Sqrt(x)/README.md) | Easy |

| 68 | [Text Justification](https://leetcode.com/problems/text-justification/) | | | Hard |

| 67 | [Add Binary](https://leetcode.com/problems/add-binary/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Binary/add-binary.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Binary/README.md) | Easy |

| 66 | [Plus One](https://leetcode.com/problems/plus-one/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Plus%20One/plus-one.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Plus%20One/README.md) | Easy |

| 65 | [Valid Number](https://leetcode.com/problems/valid-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Number/valid-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Number/README.md) | Hard |

| 64 | [Minimum Path Sum](https://leetcode.com/problems/minimum-path-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Minimum%20Path%20Sum/minimum-path-sum.js) | | Medium |

| 63 | [Unique Paths II](https://leetcode.com/problems/unique-paths-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Unique%20Paths%20II/unique-paths-ii.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Unique%20Paths%20II/README.md) | Medium |

| 62 | [Unique Paths](https://leetcode.com/problems/unique-paths/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Unique%20Paths/unique-paths.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Unique%20Paths/README.md) | Medium |

| 61 | [Rotate List](https://leetcode.com/problems/rotate-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rotate%20List/rotate-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rotate%20List/README.md) | Medium |

| 60 | [Permutation Sequence](https://leetcode.com/problems/permutation-sequence/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Permutation%20Sequence/permutation-sequence.js) | | Medium |

| 59 | [Spiral Matrix II](https://leetcode.com/problems/spiral-matrix-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Spiral%20Matrix%20II/spiral-matrix-ii.js) | | Medium |

| 58 | [Length of Last Word](https://leetcode.com/problems/length-of-last-word/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Length%20of%20Last%20Word/length-of-last-word.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Length%20of%20Last%20Word/README.md) | Easy |

| 57 | [Insert Interval](https://leetcode.com/problems/insert-interval/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Insert%20Interval/insert-interval.js) | | Hard |

| 56 | [Merge Intervals](https://leetcode.com/problems/merge-intervals/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Merge%20Intervals/merge-intervals.js) | | Medium |

| 55 | [Jump Game](https://leetcode.com/problems/jump-game/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Jump%20Game/jump-game.js) | | Medium |

| 54 | [Spiral Matrix](https://leetcode.com/problems/spiral-matrix/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Spiral%20Matrix/spiral-matrix.js) | | Medium |

| 53 | [Maximum Subarray](https://leetcode.com/problems/maximum-subarray/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Maximum%20Subarray/maximum-subarray.js) | | Easy |

| 52 | [N-Queens II](https://leetcode.com/problems/n-queens-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/N-Queens%20II/n-queens-ii.js) | | Hard |

| 51 | [N-Queens](https://leetcode.com/problems/n-queens/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/N-Queens/n-queens.js) | | Hard |

| 50 | [Pow(x, n)](https://leetcode.com/problems/powx-n/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pow(x,%20n)/powx-n.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Pow(x,%20n)/README.md) | Medium |

| 49 | [Group Anagrams](https://leetcode.com/problems/group-anagrams/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Group%20Anagrams/anagrams.js) | | Medium |

| 48 | [Rotate Image](https://leetcode.com/problems/rotate-image/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Rotate%20Image/rotate-image.js) | | Medium |

| 47 | [Permutations II](https://leetcode.com/problems/permutations-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Permutations%20II/permutations-ii.js) | | Medium |

| 46 | [Permutations](https://leetcode.com/problems/permutations/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Permutations/permutations.js) | | Medium |

| 45 | [Jump Game II](https://leetcode.com/problems/jump-game-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Jump%20Game%20II/jump-game-ii.js) | | Hard |

| 44 | [Wildcard Matching](https://leetcode.com/problems/wildcard-matching/) | | | Hard |

| 43 | [Multiply Strings](https://leetcode.com/problems/multiply-strings/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Multiply%20Strings/multiply-strings.js) | | Medium |

| 42 | [Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Trapping%20Rain%20Water/trapping-rain-water.js) | | Hard |

| 41 | [First Missing Positive](https://leetcode.com/problems/first-missing-positive/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/First%20Missing%20Positive/first-missing-positive.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/First%20Missing%20Positive/README.md) | Hard |

| 40 | [Combination Sum II](https://leetcode.com/problems/combination-sum-ii/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Combination%20Sum%20II/combination-sum-ii.js) | | Medium |

| 39 | [Combination Sum](https://leetcode.com/problems/combination-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Combination%20Sum/combination-sum.js) | | Medium |

| 38 | [Count and Say](https://leetcode.com/problems/count-and-say/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20and%20Say/count-and-say.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Count%20and%20Say/README.md) | Easy |

| 37 | [Sudoku Solver](https://leetcode.com/problems/sudoku-solver/) | | | Hard |

| 36 | [Valid Sudoku](https://leetcode.com/problems/valid-sudoku/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Sudoku/valid-sudoku.js) | | Medium |

| 35 | [Search Insert Position](https://leetcode.com/problems/search-insert-position/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20Insert%20Position/search-insert-position.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20Insert%20Position/README.md) | Easy |

| 34 | [Search for a Range](https://leetcode.com/problems/search-for-a-range/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20for%20a%20Range/search-for-a-range.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20for%20a%20Range/README.md) | Medium |

| 33 | [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Search%20in%20Rotated%20Sorted%20Array/search-in-rotated-sorted-array.js) | | Medium |

| 32 | [Longest Valid Parentheses](https://leetcode.com/problems/longest-valid-parentheses/) | | | Hard |

| 31 | [Next Permutation](https://leetcode.com/problems/next-permutation/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Next%20Permutation/next-permutation.js) | | Medium |

| 30 | [Substring with Concatenation of All Words](https://leetcode.com/problems/substring-with-concatenation-of-all-words/) | | | Hard |

| 29 | [Divide Two Integers](https://leetcode.com/problems/divide-two-integers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Divide%20Two%20Integers/divide-two-integers.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Divide%20Two%20Integers/README.md) | Medium |

| 28 | [Implement strStr()](https://leetcode.com/problems/implement-strstr/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20strStr()/implement-strstr.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Implement%20strStr()/README.md) | Easy |

| 27 | [Remove Element](https://leetcode.com/problems/remove-element/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Element/remove-element.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Element/README.md) | Easy |

| 26 | [Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Duplicates%20from%20Sorted%20Array/remove-duplicates-from-sorted-array.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Duplicates%20from%20Sorted%20Array/README.md) | Easy |

| 25 | [Reverse Nodes in k-Group](https://leetcode.com/problems/reverse-nodes-in-k-group/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Nodes%20in%20k-Group/reverse-nodes-in-k-group.js) | | Hard |

| 24 | [Swap Nodes in Pairs](https://leetcode.com/problems/swap-nodes-in-pairs/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Swap%20Nodes%20in%20Pairs/swap-nodes-in-pairs.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Swap%20Nodes%20in%20Pairs/README.md) | Medium |

| 23 | [Merge k Sorted Lists](https://leetcode.com/problems/merge-k-sorted-lists/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Merge%20k%20Sorted%20Lists/merge-k-sorted-lists.js) | | Hard |

| 22 | [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Generate%20Parentheses/generate-parentheses.js) | | Medium |

| 21 | [Merge Two Sorted Lists](https://leetcode.com/problems/merge-two-sorted-lists/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Merge%20Two%20Sorted%20Lists/merge-two-sorted-lists.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Merge%20Two%20Sorted%20Lists/README.md) | Easy |

| 20 | [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Parentheses/valid-parentheses.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Valid%20Parentheses/README.md) | Easy |

| 19 | [Remove Nth Node From End of List](https://leetcode.com/problems/remove-nth-node-from-end-of-list/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Nth%20Node%20From%20End%20of%20List/remove-nth-node-from-end-of-list.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Remove%20Nth%20Node%20From%20End%20of%20List/README.md) | Medium |

| 18 | [4Sum](https://leetcode.com/problems/4sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/4Sum/4sum.js) | | Medium |

| 17 | [Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Letter%20Combinations%20of%20a%20Phone%20Number/letter-combinations-of-a-phone-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Letter%20Combinations%20of%20a%20Phone%20Number/README.md) | Medium |

| 16 | [3Sum Closest](https://leetcode.com/problems/3sum-closest/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/3Sum%20Closest/3sum-closest.js) | | Medium |

| 15 | [3Sum](https://leetcode.com/problems/3sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/3Sum/3sum.js) | | Medium |

| 14 | [Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Common%20Prefix/longest-common-prefix.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Common%20Prefix/README.md) | Easy |

| 13 | [Roman to Integer](https://leetcode.com/problems/roman-to-integer/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Roman%20to%20Integer/roman-to-integer.js) | | Easy |

| 12 | [Integer to Roman](https://leetcode.com/problems/integer-to-roman/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Integer%20to%20Roman/integer-to-roman.js) | | Medium |

| 11 | [Container With Most Water](https://leetcode.com/problems/container-with-most-water/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Container%20With%20Most%20Water/O(nlogn).js) | | Medium |

| 10 | [Regular Expression Matching](https://leetcode.com/problems/regular-expression-matching/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Regular%20Expression%20Matching/regular-expression-matching.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Regular%20Expression%20Matching/README.md) | Hard |

| 9 | [Palindrome Number](https://leetcode.com/problems/palindrome-number/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Number/palindrome-number.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Palindrome%20Number/README.md) | Easy |

| 8 | [String to Integer (atoi)](https://leetcode.com/problems/string-to-integer-atoi/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/String%20to%20Integer%20(atoi)/string-to-integer-atoi.js) | | Medium |

| 7 | [Reverse Integer](https://leetcode.com/problems/reverse-integer/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Integer/reverse-integer.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Reverse%20Integer/README.md) | Easy |

| 6 | [ZigZag Conversion](https://leetcode.com/problems/zigzag-conversion/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/ZigZag%20Conversion/zigzag-conversion.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/ZigZag%20Conversion/README.md) | Medium |

| 5 | [Longest Palindromic Substring](https://leetcode.com/problems/longest-palindromic-substring/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Palindromic%20Substring/longest-palindromic-substring.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Palindromic%20Substring/README.md) | Medium |

| 4 | [Median of Two Sorted Arrays](https://leetcode.com/problems/median-of-two-sorted-arrays/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Median%20of%20Two%20Sorted%20Arrays/O(nlogn).js) | | Hard |

| 3 | [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Longest%20Substring%20Without%20Repeating%20Characters/longest-substring-without-repeating-characters.js) | | Medium |

| 2 | [Add Two Numbers](https://leetcode.com/problems/add-two-numbers/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Add%20Two%20Numbers/add-two-numbers.js) | | Medium |

| 1 | [Two Sum](https://leetcode.com/problems/two-sum/) | [JavaScript](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Two%20Sum/two-sum.js) | [Explanation](https://github.com/hanzichi/leetcode/blob/master/Algorithms/Two%20Sum/README.md) | Easy |