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https://github.com/prakharjadaun/dsa

Repository contains implementation of different data structures and problems related to them.
https://github.com/prakharjadaun/dsa
competitive-programming data-structures dsa-learning-series dynamic-programming implementation-of-algorithms interview leetcode-solutions placement-preparation problem-solving
Last synced: 2 months ago
JSON representation
Repository contains implementation of different data structures and problems related to them.
Host: GitHub
URL: https://github.com/prakharjadaun/dsa
Owner: prakharjadaun
License: mit
Created: 2022-07-12T06:38:04.000Z (over 2 years ago)
Default Branch: main
Last Pushed: 2024-04-06T05:25:43.000Z (10 months ago)
Last Synced: 2024-05-11T05:56:11.513Z (9 months ago)
Topics: competitive-programming, data-structures, dsa-learning-series, dynamic-programming, implementation-of-algorithms, interview, leetcode-solutions, placement-preparation, problem-solving
Language: C++
Homepage:
Size: 568 KB
Stars: 4
Watchers: 1
Forks: 0
Open Issues: 0
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project

README

        


  
 

  

  


    Master Data Structures and Algorithms with ease

  






  Arrays •

  Strings •

  Bitwise Manip. •

  Linked List •

  Queue •

  Stack •

  Hash Table •

  Sorting





    Searching •

    Recursion •

    Binary Tree •

    Binary Search Tree •

    Graph •

    Dynamic Programming





    Numbers •

    Favorites

    
Count : 471



Numbers


- [Ugly Numbers](https://leetcode.com/problems/ugly-number/description/)

- [Power of x^n](https://leetcode.com/problems/powx-n/)

- [Insert Interval](https://leetcode.com/problems/insert-interval/description/?envType=study-plan-v2&envId=top-interview-150)

- [Minimum number of arrows to burst balloons](https://leetcode.com/problems/minimum-number-of-arrows-to-burst-balloons/description/?envType=study-plan-v2&envId=top-interview-150)

- [Max points on a line](https://leetcode.com/problems/max-points-on-a-line/description/?envType=study-plan-v2&envId=top-interview-150)

Arrays


#### **Basic Programs**

- Reverse an array.

- Maximum and minimum element in the array.

- Kth Smallest Element of Array

- Sort an array of 0s, 1s and 2s

- Sort an array of 0s, 1s and 2s (two pointer approach)

- Move all negative numbers to beginning and positive to end.

- Find the count of union of the two arrays

- Rotate an array by 1 in the clockwise direction

- Print all permutations of array

- [Kids with the greatest number of candies](https://leetcode.com/problems/kids-with-the-greatest-number-of-candies/description/)

- [Create Target Array in the Given Order](https://leetcode.com/problems/create-target-array-in-the-given-order/description/)

- [Decompress run length encoded list](https://leetcode.com/problems/decompress-run-length-encoded-list/description/)

- [Count items matching a rule](https://leetcode.com/problems/count-items-matching-a-rule/description/)

- [Widest vertical area between two points](https://leetcode.com/problems/widest-vertical-area-between-two-points-containing-no-points/description/)

- [Rearranging the array elements by sign](https://leetcode.com/problems/rearrange-array-elements-by-sign/description/)

- [Largest Altitude of biker](https://leetcode.com/problems/find-the-highest-altitude/description/)

- [Count Number of Distinct Integers After Reverse](https://leetcode.com/problems/count-number-of-distinct-integers-after-reverse-operations/)

- [Triangular Sum of an array](https://leetcode.com/problems/find-triangular-sum-of-an-array/description/)

- [Jewels in Stones](https://leetcode.com/problems/jewels-and-stones/description/)

- [Minimum Sum of four digits number after splitting](https://leetcode.com/problems/minimum-sum-of-four-digit-number-after-splitting-digits/description/)

- [Intersection of Multiple Arrays](https://leetcode.com/problems/intersection-of-multiple-arrays/description/)

- [Move Zeros](https://leetcode.com/problems/move-zeroes/description/)

- [Matrix Diagonal sum](https://leetcode.com/problems/matrix-diagonal-sum/description/)

- [Flip an image](https://leetcode.com/problems/flipping-an-image/description/)

- [Missing number](https://leetcode.com/problems/missing-number/description/)

- [Happy number](https://leetcode.com/problems/happy-number/description/)

- [Maximum ice cream](https://leetcode.com/problems/maximum-ice-cream-bars/description/)

- [N unique integers which sum up to zero](https://leetcode.com/problems/find-n-unique-integers-sum-up-to-zero/description/)

- [Monotonic Array](https://leetcode.com/problems/monotonic-array/description/)

- [Largest Positive Integer That Exists With Its Negative](https://leetcode.com/problems/largest-positive-integer-that-exists-with-its-negative/description/)

- [Find Words That Can Be Formed by Characters](https://leetcode.com/problems/find-words-that-can-be-formed-by-characters/description/)

- [Sort array by parity](https://leetcode.com/problems/sort-array-by-parity/description/)

- [Separate Digits in array](https://leetcode.com/problems/separate-the-digits-in-an-array/description/)

- [Third max number](https://leetcode.com/problems/third-maximum-number/description/)

- [Is subarray Exists with sum 0](https://practice.geeksforgeeks.org/problems/subarray-with-0-sum/0)

- [Lonely Numbers in the array](https://leetcode.com/problems/find-all-lonely-numbers-in-the-array/description/)

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

- [Duplicate Zeros](https://leetcode.com/problems/duplicate-zeros/description/)

- [Shuffle an array](https://leetcode.com/problems/shuffle-an-array/description/)

- [Find winner on a tic tac toe game](https://leetcode.com/problems/find-winner-on-a-tic-tac-toe-game/description/)

- [Check if every row and column contains all numbers](https://leetcode.com/problems/check-if-every-row-and-column-contains-all-numbers/description/)

- [Roman to Integer](https://leetcode.com/problems/roman-to-integer/description/)

- [Find the Distance Value Between Two Arrays](https://leetcode.com/problems/find-the-distance-value-between-two-arrays/description/)

- [Peak Index in a mountain array](https://leetcode.com/problems/peak-index-in-a-mountain-array/description/)

- [Find a peak element](https://leetcode.com/problems/find-peak-element/description/?envType=study-plan-v2&envId=top-interview-150)

#### **Problems**

- Largest Sum Contiguous Subarray (Kadane’s Algorithm)

- Difference of two arrays

- Intersection of two arrays

- [3 Sum](https://leetcode.com/problems/3sum/description/)

- [2 Sum](https://leetcode.com/problems/two-sum/description/)

- [4 Sum](https://leetcode.com/problems/4sum/description/)

- [Palindrome](https://leetcode.com/problems/palindrome-number/description/)

- [Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/description/)

- [Length of last word](https://leetcode.com/problems/length-of-last-word/description/)

- [Plus One (adding one to an array representing a large number)](https://leetcode.com/problems/plus-one/description/)

- [Pascal's Triangle](https://leetcode.com/problems/pascals-triangle/)

- [Valid Palindrome String](https://leetcode.com/problems/valid-palindrome/description/)

- [Middle Of Threee](https://practice.geeksforgeeks.org/problems/middle-of-three2926/1?page=1&category[]=Numbers&sortBy=submissions)

- [Median of two sorted arrays](https://leetcode.com/problems/median-of-two-sorted-arrays/description/)

- [Reverse Integer](https://leetcode.com/problems/reverse-integer/description/)

- [Remove element](https://leetcode.com/problems/remove-element/description/)

- [Search in Rotated Sorted Array](https://leetcode.com/problems/search-in-rotated-sorted-array/description/)

- [3 sum closest](https://leetcode.com/problems/3sum-closest/description/)

- [Word Pattern](https://leetcode.com/problems/word-pattern/description/)

- [Sort Colors](https://leetcode.com/problems/sort-colors/description/)

- [Build array from permutation](https://leetcode.com/problems/build-array-from-permutation/description/)

- [Shuffle the array](https://leetcode.com/problems/shuffle-the-array/description/)

- [Queries on Number of Points Inside a Circle](https://leetcode.com/problems/queries-on-number-of-points-inside-a-circle/description/)

- [Strictly Palidromic Number](https://leetcode.com/problems/strictly-palindromic-number/)

- [Divide Array Into Equal Pairs](https://leetcode.com/problems/divide-array-into-equal-pairs/description/)

- [Squares of a sorted array](https://leetcode.com/problems/squares-of-a-sorted-array/description/)

- [Rotate image](https://leetcode.com/problems/rotate-image/description/)

- [Merge Intervals](https://leetcode.com/problems/merge-intervals/description/)

- [Delete Greatest Value in Each Row](https://leetcode.com/problems/delete-greatest-value-in-each-row/description/)

- [Sort the students](https://leetcode.com/problems/sort-the-students-by-their-kth-score/description/)

- [Largest Number](https://leetcode.com/problems/largest-number/description/)

- [Sort the number of 1 bits](https://leetcode.com/problems/sort-integers-by-the-number-of-1-bits/description/)

- [Check if matrix is X-matrix](https://leetcode.com/problems/check-if-matrix-is-x-matrix/description/)

- [Group anagrams](https://leetcode.com/problems/group-anagrams/description/)

- [Add to array form](https://leetcode.com/problems/add-to-array-form-of-integer/description/)

- [Find all the numbers that disappeared in an array](https://leetcode.com/problems/find-all-numbers-disappeared-in-an-array/description/)

- [Rotate the array](https://leetcode.com/problems/rotate-array/description/)

- [Find lucky number](https://leetcode.com/problems/find-lucky-integer-in-an-array/description/)

- [Contains Duplicate II](https://leetcode.com/problems/contains-duplicate-ii/description/)

- Disarrange Balls

- [Count rows with max 1](https://practice.geeksforgeeks.org/problems/row-with-max-1s0023/1)

- [Relative Sort Array](https://leetcode.com/problems/relative-sort-array/description/)

- [Remove One Element to Make the Array Strictly Increasing](https://leetcode.com/problems/remove-one-element-to-make-the-array-strictly-increasing/description/)

- [Successful pairs of potions and spells](https://leetcode.com/problems/successful-pairs-of-spells-and-potions/description/)

- [Valid mountain array](https://leetcode.com/problems/valid-mountain-array/)

- [Longest mountain array](https://leetcode.com/problems/longest-mountain-in-array/description/)

#### **Matrix**

- [Matrix rotation by 90 degree](https://leetcode.com/problems/rotate-image/?envType=study-plan-v2&envId=top-interview-150)

- [Set Matrix Zeros](https://leetcode.com/problems/set-matrix-zeroes/description/?envType=study-plan-v2&envId=top-interview-150)

- [Spiral Matrix](https://leetcode.com/problems/spiral-matrix/description/?envType=study-plan-v2&envId=top-interview-150)

- [Reshape the matrix](https://leetcode.com/problems/reshape-the-matrix/description/)

- [Search in a matrix](https://leetcode.com/problems/search-a-2d-matrix/description/?envType=study-plan-v2&envId=top-interview-150)

- [Is Valid Sudoku](https://leetcode.com/problems/valid-sudoku/submissions/?envType=study-plan-v2&envId=top-interview-150)

- [Sort the matrix diagonally](https://leetcode.com/problems/sort-the-matrix-diagonally/description/)

Strings


- String Basics

- Print all permutations of the string

- Subsequences of string

- Longest recurring subsequence of a string

- [Add Binary](https://leetcode.com/problems/add-binary/description/)

- [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/description/)

- [Find the Index of the First Occurrence in a String](https://leetcode.com/problems/find-the-index-of-the-first-occurrence-in-a-string/)

- [Maximum number of words found in a sentence](https://leetcode.com/problems/maximum-number-of-words-found-in-sentences/description/)

- [Defang Ip address](https://leetcode.com/problems/defanging-an-ip-address/description/)

- [Restore strings](https://leetcode.com/problems/shuffle-string/description/)

- [Interpret Goal](https://leetcode.com/problems/goal-parser-interpretation/description/)

- [Kth Distinct String in an Array](https://leetcode.com/problems/kth-distinct-string-in-an-array/description/)

- [Merge strings alternatively](https://leetcode.com/problems/merge-strings-alternately/description/)

- [Valid anagram](https://leetcode.com/problems/valid-anagram/description/)

- [Find the difference](https://leetcode.com/problems/find-the-difference/description/)

- [First Unique Character in a String](https://leetcode.com/problems/first-unique-character-in-a-string/description/)

- [Number of good ways to split a string](https://leetcode.com/problems/number-of-good-ways-to-split-a-string/description/)

- [Counting words with a given prefix](https://leetcode.com/problems/counting-words-with-a-given-prefix/description/)

- [Greatest common divisor of strings](https://leetcode.com/problems/greatest-common-divisor-of-strings/description/)

- [Check distance between same letters](https://leetcode.com/problems/check-distances-between-same-letters/description/)

- [Number of different integers in the string](https://leetcode.com/problems/number-of-different-integers-in-a-string/description/)

- [Check whether two string are rotation of each other or not](https://www.geeksforgeeks.org/a-program-to-check-if-strings-are-rotations-of-each-other/)

- [Longest Palindromic Substring](https://practice.geeksforgeeks.org/problems/longest-palindrome-in-a-string3411/1)

- [Most common words](https://leetcode.com/problems/most-common-word/description/)

- [DI String match](https://leetcode.com/problems/di-string-match/description/)

- [Count prefixes of a given string](https://leetcode.com/problems/count-prefixes-of-a-given-string/description/)

- [Sort Characters By Frequency](https://leetcode.com/problems/sort-characters-by-frequency/description/)

- [Count Common Words With One Occurrence](https://leetcode.com/problems/count-common-words-with-one-occurrence/description/)

- [Rearrange Characters to Make Target String](https://leetcode.com/problems/rearrange-characters-to-make-target-string/description/)

- [Unique Morse Code Words](https://leetcode.com/problems/unique-morse-code-words/description/)

- [Percentage of a letter](https://leetcode.com/problems/percentage-of-letter-in-string/description/)

- [Check if Word Equals Summation of Two Words](https://leetcode.com/problems/check-if-word-equals-summation-of-two-words/description/)

- [Check if Number Has Equal Digit Count and Digit Value](https://leetcode.com/problems/check-if-number-has-equal-digit-count-and-digit-value/description/)

- [Circular Sentence](https://leetcode.com/problems/circular-sentence/description/)

- [Isomorphic strings](https://leetcode.com/problems/isomorphic-strings/description/)

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

- [Greatest English Letter in Upper and Lower Case](https://leetcode.com/problems/greatest-english-letter-in-upper-and-lower-case/description/)

- [Second largest digit in a string](https://leetcode.com/problems/second-largest-digit-in-a-string/description/)

- [Sort a sentence](https://leetcode.com/problems/sorting-the-sentence/description/)

- [Summary ranges](https://leetcode.com/problems/summary-ranges/description/)

- [Robot return to origin](https://leetcode.com/problems/robot-return-to-origin/description/)

- [Maximum Nesting Depth of the Parentheses](https://leetcode.com/problems/maximum-nesting-depth-of-the-parentheses/description/)

- [Reverse prefix of word](https://leetcode.com/problems/reverse-prefix-of-word/description/)

- [Determine color of a chessboard square](https://leetcode.com/problems/determine-color-of-a-chessboard-square/description/)

- [Partition String](https://leetcode.com/problems/optimal-partition-of-string/description/)

- [Minimum number of steps to make two strings anagram](https://leetcode.com/problems/minimum-number-of-steps-to-make-two-strings-anagram/description/)

- [Goat Latin](https://leetcode.com/problems/goat-latin/description/)

- [Smallest string with a given numeric value](https://leetcode.com/problems/smallest-string-with-a-given-numeric-value/description/)

- [Check if a word occurs as a prefix of any word in a sentence](https://leetcode.com/problems/check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence/description/)

- [Count pairs of similar strings](https://leetcode.com/problems/count-pairs-of-similar-strings/description/)

- [Add string](https://leetcode.com/problems/add-strings/description/)

- [Is Subsequence](https://leetcode.com/problems/is-subsequence/description/?envType=study-plan-v2&envId=top-interview-150)

- [Buddy Strings](https://leetcode.com/problems/buddy-strings/description/)

- [Bulls and cows](https://leetcode.com/problems/bulls-and-cows/description/)

Bitwise Operations


- Understanding Bitwise operators.

- Binary Representation of number.

- [Find the number that appears once.](https://leetcode.com/problems/single-number/description/)

- [Detect if two integers have opposite signs](https://www.geeksforgeeks.org/detect-if-two-integers-have-opposite-signs/)

- [Add 1 to a number when all the arithmetic operators are not allowed](https://www.geeksforgeeks.org/add-1-to-a-given-number/)

- [Mutliply with 3.5 without 'x' and '/' operator](https://www.geeksforgeeks.org/multiply-an-integer-with-3-5/)

- [Turn off the rightmost set bit](https://www.geeksforgeeks.org/turn-off-the-rightmost-set-bit/)

- [Find whether a given number is a power of 4 or not](https://www.geeksforgeeks.org/find-whether-a-given-number-is-a-power-of-4-or-not/#discuss)

- [Compute modulus division by a power-of-2-number](https://www.geeksforgeeks.org/compute-modulus-division-by-a-power-of-2-number/)

- [Rotate Bits](https://practice.geeksforgeeks.org/problems/rotate-bits4524/1?utm_source=gfg)

- [Hamming weights (Number of 1 bits)](https://leetcode.com/problems/number-of-1-bits/description/)

- [Reverse Bits](https://leetcode.com/problems/reverse-bits/description/)

- [Power Of two](https://leetcode.com/problems/power-of-two/description/)

- [Bitwise & of numbers in range](https://leetcode.com/problems/bitwise-and-of-numbers-range/description/)

- [Find the duplicate number](https://leetcode.com/problems/find-the-duplicate-number/)

- [Party of couples (Find number with odd frequency)](https://practice.geeksforgeeks.org/problems/alone-in-couple5507/1)

- [Check for Integer Overflow](https://www.geeksforgeeks.org/check-for-integer-overflow/)

- [Count bit flips(Number of bits to be changed to convert one number to another)](https://practice.geeksforgeeks.org/problems/bit-difference-1587115620/1)

- [Efficient way to multiply by 7](https://www.geeksforgeeks.org/efficient-way-to-multiply-with-7/)

Linked List


#### **Basic Programs**

- Insertion at the end.

- Insertion at the beginning.

- Insertion at the middle of the linked list.

- Deleting the last node.

- Deleting the first node.

- Deleting the middle node.

- Calculating the length of list using iteration and the recursion.

- Searching an item using iteration and recursion.

- Implementation of doubly linked list.

#### **Circular Linked List**

- Creating a circular linked list from scratch.

- Inserting at end and beginning of the circular linked list

- Deleting the last and the first element of the circular linked list.

#### **Problems**

- Get the Nth node from the last.

- Detecting a loop in a linked list.

- Detecting the length of loop in a linked list. (Using Floyd's Cycle detection algorithm)

- Detect and remove loop from the linked list.

- Check if single linked list is palindrome or not.

- Removing Duplicate elements from unsorted linked list.

- Swapping nodes in a linked list.

- Merge two sorted linked list.

- Add two numbers represented by linked list.

- Rotate a linked list.

- Find the nth node of the linked list from the end.

- Convert binary number in a linked list to an integer.

- [Merge nodes in between zeros](https://leetcode.com/problems/merge-nodes-in-between-zeros/)

- [Maximum twin sum](https://leetcode.com/problems/maximum-twin-sum-of-a-linked-list/description/)

- [Odd even linked list](https://leetcode.com/problems/odd-even-linked-list/description/)

- [Remove Linked List Elements](https://leetcode.com/problems/remove-linked-list-elements/description/)

- [Design linked list](https://leetcode.com/problems/design-linked-list/description/)

- [Reorder List](https://leetcode.com/problems/reorder-list/description/)

- [Swap nodes in pairs](https://leetcode.com/problems/swap-nodes-in-pairs/description/)

- [Reverse Linked List II](https://leetcode.com/problems/reverse-linked-list-ii/description/)

- [Copy Linked list with Random Head](https://leetcode.com/problems/copy-list-with-random-pointer/description/?envType=study-plan-v2&envId=top-interview-150)

- [Remove Duplicates from Sorted List II](https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/description/?envType=study-plan-v2&envId=top-interview-150)

- [Intersection of two linked list](https://practice.geeksforgeeks.org/problems/intersection-of-two-sorted-linked-lists/1)

- [Remove nth node from the end of linked list](https://leetcode.com/problems/remove-nth-node-from-end-of-list/description/)

- [Reverse List in K Groups](https://leetcode.com/problems/reverse-nodes-in-k-group/submissions/?envType=study-plan-v2&envId=top-interview-150)

- [Flatten a multilevel doubly linked list](https://leetcode.com/problems/flatten-a-multilevel-doubly-linked-list/description/)

- [Next Greater Node in the Linked List](https://leetcode.com/problems/next-greater-node-in-linked-list/description/)

- [Double a number represented by a linked list](https://leetcode.com/problems/double-a-number-represented-as-a-linked-list/)

Queue


#### **Basic Program**

- Basic operations of queue

- Queue using stack.

- Priority Queue using STL.

- Priority Queue using linked list.

#### **Problems**

- [Kth Smallest element in a matrix](https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix/description/)

- [Design a circular queue](https://leetcode.com/problems/design-circular-deque/)

Hash Table


#### **Basic Programs**

- [Create Hashset](https://leetcode.com/problems/design-hashset/)

- [Create Hashmap](https://leetcode.com/problems/design-hashmap/description/)

- [Most Frequent number of following key in an array](https://leetcode.com/problems/most-frequent-number-following-key-in-an-array/description/)

- [Keyboard Row](https://leetcode.com/problems/keyboard-row/description/)

- [Uncommon Words from Two Sentences](https://leetcode.com/problems/uncommon-words-from-two-sentences/description/)

- [N-Repeated Element in Size 2N Array](https://leetcode.com/problems/n-repeated-element-in-size-2n-array/description/)

- [Rank Transform of an Array](https://leetcode.com/problems/rank-transform-of-an-array/description/)

#### **Problems**

- Find whether an array is a subset of another array

- Union and Intersection of two linked list.

- Given an array A[] and a number x, check for pair in A[] with sum as x

- Minimum delete operations to make all elements of array same.

- Minimum operations to make all elements equal in array.

- Maximum distance between two occurrences of same element in array

- Find duplicates in a given array when elements are not limited to a range

- Smallest subarray with all occurrences of a most frequent element.

- Find elements which are present in first array and not in second array.

- How to check if two subsets are disjoint.

- Non-overlapping sum of two sets.

- Find missing elements of a range.

- Find the kth missing element in increasing sequence which is not present in a given sequence

- Find pair with greatest pair in array.

- Minimum number of subsets with distinct elements

- Remove minimum number of elements such that no common element exist in both array.

- Count items common to both the lists but with different prices.

- Ransom Note : check whether string 1 can be constructed from string 2

- [Decode the message](https://leetcode.com/problems/decode-the-message/description/)

- [Maximum Number of Words You Can Type](https://leetcode.com/problems/maximum-number-of-words-you-can-type/description/)

- [Check if a string is pangram](https://leetcode.com/problems/check-if-the-sentence-is-pangram/description/)

- [Merge similar items](https://leetcode.com/problems/merge-similar-items/description/)

- [Maximum number of balls in a box](https://leetcode.com/problems/maximum-number-of-balls-in-a-box/description/)

- [Two out of three](https://leetcode.com/problems/two-out-of-three/description/)

- [Sort array by increaing frequency](https://leetcode.com/problems/sort-array-by-increasing-frequency/description/)

- [Top K frequent elements](https://leetcode.com/problems/top-k-frequent-elements/description/)

- [https://leetcode.com/problems/count-vowel-substrings-of-a-string/description/](https://leetcode.com/problems/count-vowel-substrings-of-a-string/description/)

- [Replace words](https://leetcode.com/problems/replace-words/description/)

- [Keep Multiplying Found Values by Two](https://leetcode.com/problems/keep-multiplying-found-values-by-two/description/)

- [Most Frequent Even Element](https://leetcode.com/problems/most-frequent-even-element/description/)

- [Rings and Rods](https://leetcode.com/problems/rings-and-rods/description/)

- [Finding the user active minutes](https://leetcode.com/problems/finding-the-users-active-minutes/description/)

- [Subdomain Visit Counts](https://leetcode.com/problems/subdomain-visit-count/description/)

- [Players with zero or one losses](https://leetcode.com/problems/find-players-with-zero-or-one-losses/description/)

- [Equal row and column pairs](https://leetcode.com/problems/equal-row-and-column-pairs/description/)

- [Check whether two strings are almost equivalent](https://leetcode.com/problems/check-whether-two-strings-are-almost-equivalent/description/)

- [Distribute candies](https://leetcode.com/problems/distribute-candies/description/)

- [Smallest number in infinite set](https://leetcode.com/problems/smallest-number-in-infinite-set/description/)

- [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/description/?envType=study-plan-v2&envId=top-interview-150)

- [Insert delete get random in O(1)](https://leetcode.com/problems/insert-delete-getrandom-o1/description/)

- [Design Underground System](https://leetcode.com/problems/design-underground-system/description/)

Stack


#### **Basic programs**

- Basic operations of stack.

- Implementing stack using queues.

- Reverse a string using stack.

#### **Problems**

- Find the middle element of the stack in O(1) complexity.

- Implement stack using a single queue.

- Reverse individual words.

- Next Greater Element

- [Next Smaller Element](https://www.codingninjas.com/codestudio/problems/next-smaller-element_1112581?leftPanelTab=0)

- Valid parenthesis

- [Minimum remove to make valid parentheses](https://leetcode.com/problems/minimum-remove-to-make-valid-parentheses/description/?envType=daily-question&envId=2024-04-06)

- [Design a stack with increment operation](https://leetcode.com/problems/design-a-stack-with-increment-operation/description/)

- [Baseball game](https://leetcode.com/problems/baseball-game/description/)

- [Min stack](https://leetcode.com/problems/min-stack/description/)

- [Removing stars from a string](https://leetcode.com/problems/removing-stars-from-a-string/description/)

- [Simply Path](https://leetcode.com/problems/simplify-path/description/?envType=study-plan-v2&envId=top-interview-150)

- [Evaluate Reverse Polish Notation](https://leetcode.com/problems/evaluate-reverse-polish-notation/description/?envType=study-plan-v2&envId=top-interview-150)

- [Remove outer parentheses](https://leetcode.com/problems/remove-outermost-parentheses/description/)

Sorting


#### **Types of Sorting Algo and their uses**

- Bubble Sort

- Insertion Sort

- Heap Sort

- [Merge Sort](https://www.codingninjas.com/studio/problems/merge-sort_920442)

- [Quick sort](https://www.codingninjas.com/studio/problems/quick-sort_983625)

#### **Problems**

- [Smaller number than current](https://leetcode.com/problems/how-many-numbers-are-smaller-than-the-current-number/description/)

- [H index](https://leetcode.com/problems/h-index/description/?envType=study-plan-v2&envId=top-interview-150)

- [Count Inversions (Merge Sort)](https://www.codingninjas.com/studio/problems/count-inversions_615?leftPanelTab=0)

Searching


- Unordered Linear Search

- Ordered Linear Search

- Binary Search

- Interpolation search

#### **Problems**

- Maximum frequency of an element in array

Recursion


#### **Basic Programs**

- Factorial using recursion

- Print numbers 1 to N in backwards

- Fibonacci Series

- Binary Search

#### **Problems**

- [N Queens problem I](https://leetcode.com/problems/n-queens/description/)

- [Combination sum](https://leetcode.com/problems/combination-sum/description/)

- [Fair Distribution of Cookies](https://leetcode.com/problems/fair-distribution-of-cookies/description/)

- [Generate Parentheses](https://leetcode.com/problems/generate-parentheses/description/)

Backtracking


#### **Problems**

- Max Num Of Requests

- [Letter combination of phone numbers](https://leetcode.com/problems/letter-combinations-of-a-phone-number/description/)

- [Combinations](https://leetcode.com/problems/combinations/description/)

- [Combination sum II](https://leetcode.com/problems/combination-sum-ii/description/)

- [Subsets](https://leetcode.com/problems/subsets/description/)

Binary Tree


#### **Basic Operations**

- Creation of Binary Tree

- Traversal in trees : PreOrder, Inorder and Postorder

- Number of nodes in tree

- Level Order Traversal Using Queue

- Deleting a binary tree

- Compute the height of the binary tree using recursion.

- Compute the height of the binary tree without recursion.

- Number of leaf nodes in a binary tree.

- [Diameter Of Binary Tree](https://leetcode.com/problems/diameter-of-binary-tree/description/)

- [PreOrder Traversal without recursion](https://leetcode.com/problems/binary-tree-preorder-traversal/description/)

- [Level order traversal II](https://leetcode.com/problems/binary-tree-level-order-traversal-ii/description/)

- [Find a Corresponding Node of a Binary Tree in a Clone of That Tree](https://leetcode.com/problems/find-a-corresponding-node-of-a-binary-tree-in-a-clone-of-that-tree/description/)

- [Deepest Leave Sum](https://leetcode.com/problems/deepest-leaves-sum/description/)

- [To sum tree](https://practice.geeksforgeeks.org/problems/transform-to-sum-tree/1)

- [Boundary Traversal](https://practice.geeksforgeeks.org/problems/boundary-traversal-of-binary-tree/0)

- [Top view](https://www.codingninjas.com/codestudio/problems/top-view-of-the-tree_799401?leftPanelTab=0)

- [Bottom View](https://www.codingninjas.com/codestudio/problems/bottom-view-of-binary-tree_893110?leftPanelTab=0)

- [Diagonal traversal](https://www.codingninjas.com/studio/problems/diagonal-traversal-of-a-binary-tree_920477?leftPanelTab=0)

- [Leaf at same level](https://practice.geeksforgeeks.org/problems/leaf-at-same-level/1)

  

#### **Problems**

- Mirror of the tree.

- Preorder Traversal Without Recursion.

- Find the maximum element of the binary tree using recursion.

- Find the maximum element of the bianry tree without recursion.

- Algorithm to search an element in a bianry tree.

- Algorithm to search an element in a binary tree without recursion.

- Finding the deepest node in a binary tree.

- Deletion in binary tree.

- Check if two binary trees are structurally identical.

- Find level with max sum.

- Find the sum of all the nodes in a binary tree.

- Check if two binary trees are mirror of each other.

- Print All Ancestors of a node.

- Print right view of the tree using level order traversal

- [Zigzag level order traversal](https://leetcode.com/problems/binary-tree-zigzag-level-order-traversal/description/)

- [Flatten binary tree to linked list](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/description/)

- [Construct string from binary tree(Parethesis)](https://leetcode.com/problems/construct-string-from-binary-tree/description/)

- [Reverse odd levels](https://leetcode.com/problems/reverse-odd-levels-of-binary-tree/description/)

- [Find Elements in a Contaminated Binary Tree](https://leetcode.com/problems/find-elements-in-a-contaminated-binary-tree/description/)

- [Remove leaf nodes with a given value](https://leetcode.com/problems/delete-leaves-with-a-given-value/description/)

- [Evaluate a boolean binary tree](https://leetcode.com/problems/evaluate-boolean-binary-tree/description/)

- [Increasing Order Search Tree](https://leetcode.com/problems/increasing-order-search-tree/description/)

- [Average of levels of binary tree](https://leetcode.com/problems/average-of-levels-in-binary-tree/description/)

- [Leaf similar trees](https://leetcode.com/problems/leaf-similar-trees/description/)

- [Binary Tree tilt](https://leetcode.com/problems/binary-tree-tilt/description/)

- [Find Bottom Left Tree Value](https://leetcode.com/problems/find-bottom-left-tree-value/description/)

- [Has Path Sum](https://leetcode.com/problems/path-sum/description/?envType=study-plan-v2&envId=top-interview-150)

- [Populating Next Right Pointers in Each Node II](https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/description/?envType=study-plan-v2&envId=top-interview-150)

- [Sum of left leaves](https://leetcode.com/problems/sum-of-left-leaves/description/)

- [Binary Trees Max Path Sum](https://leetcode.com/problems/binary-tree-maximum-path-sum/description/)

- [Lowest Common Ancestor](https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/description/)

- [Minimum Depth of binary tree](https://leetcode.com/problems/minimum-depth-of-binary-tree/description/)

- [All nodes distance k in binary tree](https://leetcode.com/problems/all-nodes-distance-k-in-binary-tree/description/)

- [Count complete tree nodes](https://leetcode.com/problems/count-complete-tree-nodes/description/?envType=study-plan-v2&envId=top-interview-150)

- [Count Nodes Equal to Average of subtree](https://leetcode.com/problems/count-nodes-equal-to-average-of-subtree/description/)

Binary Search Tree


#### **Basic Operations**

- Creating a binary search tree.

- Find the maximum and the minimum element of the binary search tree

- Searching in the binary search tree

- Printing the InOrder Predecessor and Successor of an element.

#### **Problems**

- [Validate BST](https://leetcode.com/problems/validate-binary-search-tree/)

- [Convert Sorted Array to BST](https://leetcode.com/problems/convert-sorted-array-to-binary-search-tree/)

- [Kth Smallest element in BST](https://leetcode.com/problems/kth-smallest-element-in-a-bst/description/)

- [Mode in BST](https://leetcode.com/problems/find-mode-in-binary-search-tree/description/)

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

- [Combining elements of two BST in ascending order](https://leetcode.com/problems/all-elements-in-two-binary-search-trees/)

- [Convert BST to Greater Tree](https://leetcode.com/problems/convert-bst-to-greater-tree/description/)

- [Range Sum of BST](https://leetcode.com/problems/range-sum-of-bst/description/)

- [Unique BSTs (catalan numbers)](https://leetcode.com/problems/unique-binary-search-trees/description/)

- [Binary Search Tree Iterator](https://leetcode.com/problems/binary-search-tree-iterator/description/?envType=study-plan-v2&envId=top-interview-150)

Graph


#### **Basic programs**

- Creation of adjacency matrix

- Creation of adjacency list

- Using adjacency list to store the weights

- Tranpose of adjacency list

- Breadth first search implementation using queue & adjacency matrix

- Depth first search implementation using stack

- BFS using adjacency list

- DFS using adjacency list

- [Prims Algo](https://www.codingninjas.com/codestudio/problem-details/prim-s-mst_1095633)

- [Detect Cycle in directed graph](https://practice.geeksforgeeks.org/problems/detect-cycle-in-a-directed-graph/1)

- [Detect Cycle in directed graph (Using Topological Sort)](https://practice.geeksforgeeks.org/problems/detect-cycle-in-a-directed-graph/1)

- [Find the center of Star Graph](https://leetcode.com/problems/find-center-of-star-graph/description/)

- [Dijsktra Algo using priority queue](https://www.geeksforgeeks.org/problems/implementing-dijkstra-set-1-adjacency-matrix/1)

- [Dijsktra Algo using set](https://www.geeksforgeeks.org/problems/implementing-dijkstra-set-1-adjacency-matrix/1)

- [Bellman ford algo](https://www.geeksforgeeks.org/problems/distance-from-the-source-bellman-ford-algorithm/1)

- [Floyd warshall algo](https://www.geeksforgeeks.org/problems/implementing-floyd-warshall2042/1)

#### **Problems**

- Connected Components

- [Number of provinces](https://leetcode.com/problems/number-of-provinces/description/)

- [Number of islands](https://leetcode.com/problems/number-of-islands/description/)

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

- [Rotten Oranges](https://leetcode.com/problems/rotting-oranges/description/)

- [Detect a cycle in undirected graph](https://practice.geeksforgeeks.org/problems/detect-cycle-in-an-undirected-graph/1)

- [01 Matrix (distance to nearest 0)](https://leetcode.com/problems/01-matrix/description/)

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

- [Number of Enclaves](https://leetcode.com/problems/number-of-enclaves/description/)

- [Number of unique islands](https://practice.geeksforgeeks.org/problems/number-of-distinct-islands/1)

- [Eventual Safe State](https://practice.geeksforgeeks.org/problems/eventual-safe-states/1)

- [Topological Sort Using DFS](https://practice.geeksforgeeks.org/problems/topological-sort/1?utm_source=gfg&utm_medium=article&utm_campaign=bottom_sticky_on_article)

- [Topological Sort using Kahns Algo (BFS)](https://practice.geeksforgeeks.org/problems/topological-sort/1?utm_source=gfg&utm_medium=article&utm_campaign=bottom_sticky_on_article)

- [Course Schedule (Topological Sort)](https://leetcode.com/problems/course-schedule/description/)

- [Course Schedule II](https://leetcode.com/problems/course-schedule-ii/description/)

- [Alien Dictionary](https://practice.geeksforgeeks.org/problems/alien-dictionary/1)

- [Shortest Path in Direct Acyclic Graph(toposort approach)](https://practice.geeksforgeeks.org/problems/shortest-path-in-undirected-graph/1)

- [Shortest path in undirected graph having unit distance](https://www.geeksforgeeks.org/problems/shortest-path-in-undirected-graph-having-unit-distance/1)

- [All path from source](https://leetcode.com/problems/all-paths-from-source-to-target/description/)

- [Can Visit All Rooms](https://leetcode.com/problems/keys-and-rooms/description/)

- [Word Search](https://leetcode.com/problems/word-search/description/)

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

Dynamic Programming


- Fibonacci Numbers

  - Recursive approach

  - Memoization approach

  - Dynamic approach

  - Space optimized approach

- Catalan Numbers

  - Recursive approach  

  - DP approach

  - Binomial coefficient approach

  - [Nth Catalan number](https://practice.geeksforgeeks.org/problems/nth-catalan-number0817/1)

- Minimum operations

  - [Minimum steps to reach k from 0](https://www.geeksforgeeks.org/minimize-steps-to-reach-k-from-0-by-adding-1-or-doubling-at-each-step/)

  - [Minimum steps to reach 0 from k](https://leetcode.com/problems/number-of-steps-to-reduce-a-number-to-zero/)

- Coin change

  - [Recursive Approach](https://www.geeksforgeeks.org/coin-change-dp-7/)

  - [Space Optimized Approach](https://www.geeksforgeeks.org/coin-change-dp-7/)

- Permutations

  - [Recursive Approach](https://www.geeksforgeeks.org/write-a-c-program-to-print-all-permutations-of-a-given-string/)

  - [STL C++ Approach](https://www.geeksforgeeks.org/stdnext_permutation-prev_permutation-c/)

- [Number of ways to cover distance](https://practice.geeksforgeeks.org/problems/count-number-of-hops-1587115620/1?utm_source=gfg&utm_medium=article&utm_campaign=bottom_sticky_on_article)

  - [Recursive approach](https://www.geeksforgeeks.org/count-number-of-ways-to-cover-a-distance/)

  - [Dynamic approach](https://www.geeksforgeeks.org/count-number-of-ways-to-cover-a-distance/)

  - [More efficient approach (using array of 3)](https://www.geeksforgeeks.org/count-number-of-ways-to-cover-a-distance/)

- Longest Common Subsequence

  - [Min Insertions and deletions to make strings equal](https://www.geeksforgeeks.org/minimum-number-deletions-insertions-transform-one-string-another/)

  - [Longest Common subsequence - leetcode](https://leetcode.com/problems/longest-common-subsequence/description/)

- [Frog Jump](https://www.codingninjas.com/codestudio/problem-details/frog-jump_3621012)

  - Recursive approach

  - Memoization approach

  - Dynamic approach

  - Space optimized approach

#### **Problems**

- [Nth Tribonacci Number](https://leetcode.com/problems/n-th-tribonacci-number/description/)

- [Min cost climbing stairs](https://leetcode.com/problems/min-cost-climbing-stairs/description/)

- [Jump Game](https://leetcode.com/problems/jump-game/description/?envType=study-plan-v2&envId=top-interview-150)

- [Factorial Trailing Zeroes](https://leetcode.com/problems/factorial-trailing-zeroes/description/?envType=study-plan-v2&envId=top-interview-150)

- [Put Marbles in Bags](https://leetcode.com/problems/put-marbles-in-bags/description/)

Favorites


- [Find Duplicates](https://leetcode.com/problems/find-all-duplicates-in-an-array/description/)

- [Xor Beauty](https://leetcode.com/problems/find-xor-beauty-of-array/description/)

- ['Verifying an alien dictionary'](https://leetcode.com/problems/verifying-an-alien-dictionary/description/)

- [Zigzag Conversion](https://leetcode.com/problems/zigzag-conversion/description/)

- [Permutations in string](https://leetcode.com/problems/permutation-in-string/description/)

- [Find All Anagrams in a String](https://leetcode.com/problems/find-all-anagrams-in-a-string/description/)

- [Total fruits](https://leetcode.com/problems/fruit-into-baskets/description/)

- [Maximum number of balloons](https://leetcode.com/problems/maximum-number-of-balloons/description/)

- [Jump Game II](https://leetcode.com/problems/jump-game-ii/description/)

- [Naming a company](https://leetcode.com/problems/naming-a-company/description/)

- [As Far from Land as Possible](https://leetcode.com/problems/as-far-from-land-as-possible/description/)

- [Count Odd Numbers in an Interval Range](https://leetcode.com/problems/count-odd-numbers-in-an-interval-range/description/)

- [Replace Elements with Greatest Element on Right Side](https://leetcode.com/problems/replace-elements-with-greatest-element-on-right-side/description/)

- [Missing Number](https://practice.geeksforgeeks.org/problems/missing-number-in-array1416/1)

- [Max Product Of Subarray](https://leetcode.com/problems/maximum-product-subarray/description/)

- [Boats to save people](https://leetcode.com/problems/boats-to-save-people/description/)

- [Minimize & maximum of array](https://leetcode.com/problems/minimize-maximum-of-array/description/)

- [Teemo Attacking](https://leetcode.com/problems/teemo-attacking/description/)

- [Divisor Game](https://leetcode.com/problems/divisor-game/description/)

- [Sqrt(x)](https://leetcode.com/problems/sqrtx/description/?envType=study-plan-v2&envId=top-interview-150)

- [LRU Cache](https://leetcode.com/problems/lru-cache/description/?envType=study-plan-v2&envId=top-interview-150)

- [First missing positive](https://leetcode.com/problems/first-missing-positive/description/)

- [Frequency of limited range elements](https://practice.geeksforgeeks.org/problems/frequency-of-array-elements-1587115620/1)

- [wo Sum II - Input Array Is Sorted](https://leetcode.com/problems/two-sum-ii-input-array-is-sorted/description/)

- [Excel Sheet Column Number](https://leetcode.com/problems/excel-sheet-column-number/description/)