https://github.com/summerrainet2008/python_algorithms_library

Migrating popular data structures and algorithms in C++ to Python, such as linked list, balanced search tree, heap with a support of updating and deletion, as well as other commonly used small functions.
https://github.com/summerrainet2008/python_algorithms_library

algorithm list python tree

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Migrating popular data structures and algorithms in C++ to Python, such as linked list, balanced search tree, heap with a support of updating and deletion, as well as other commonly used small functions.

• Host: GitHub
• URL: https://github.com/summerrainet2008/python_algorithms_library
• Owner: SummerRainET2008
• Created: 2023-10-28T07:41:15.000Z (about 2 years ago)
• Default Branch: main
• Last Pushed: 2025-07-13T16:41:10.000Z (6 months ago)
• Last Synced: 2025-09-29T08:09:15.255Z (4 months ago)
• Topics: algorithm, list, python, tree
• Language: Python
• Homepage:
• Size: 217 KB
• Stars: 4
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

          
# PYthon Algorithms Library (pyal)

Unlike the STL in C++ which provides misceneous data structures, Python does not have some important structures, like `linked list`, `tree map`. 

This library aims to provide a python counterpart of C++ STL.

# 1. Install 

 ```bash

 python3 -m pip install Python-Algorithm-pyal psutil pytz

 ```

# 2. Examples [github](https://github.com/SummerRainET2008/PYthon_Algorithms_Library)

Balanced search tree based map, ```TreeMap```

```python

import pyal

def main():

  tree_map = pyal.TreeMap()

  data = [(0, "a"), (1, "b"), (2, "c"), (3, "d"), (4, "e"), (5, "f")]

  for key, value in data:

    tree_map[key] = value

  key = -1

  value = tree_map.get(key)

  if value is None:

    print(f"key={key} does not exist")

  key = 0

  print(f"key={key}, value={tree_map[key]}")

  key = 1

  node = tree_map.lower_bound(key)

  print(f"lower_bound({key=}): {node.get()=}")

  node = tree_map.upper_bound(key)

  print(f"upper_bound({key=}): {node.get()=}")

  print(f"min key: {tree_map.key_list_begin().get()}")

  print(f"max key: {tree_map.key_list_end().prev().get()}")

```

Output

```

key=-1 does not exist

key=0, value=a

lower_bound(key=1): node.get()=1

upper_bound(key=1): node.get()=2

min key: 0

max key: 5

```

# 3. Popular data structures and algorithms.

  Please check [github](https://github.com/SummerRainET2008/PYthon_Algorithms_Library) for all examples.

  * ### Tree

    >* TreeMap [example](doc/example_TreeMap.md)

    >   * ___Balanced___ binary search tree.

    >   * ___insert___ & ___delete___: O(log N)

    >   * ___get___:  O(1)

    >* DynamicHeap [example](doc/example_DynamicHeap.md)

    >   * ___update___ & ___deletion___: O(log N)

    >* MinHeap, MaxHeap [example](doc/example_MinHeap.md)

    >* DisjointSet [example](doc/example_DisjointSet.md)

  * ### List

    > * LinkedList [example](doc/example_LinkedList.md)

    > * Queue [example](doc/example_Queue.md)

    > * Dequeue [example](doc/example_Deque.md)

    > * Stack [example](doc/example_Stack.md)

    > * LRUCache [example](doc/example_LRUCache.md)

    >   * ___get___ & ___set___: O(1)

    > * LFUCache [example](doc/example_LFUCache.md)

    >   * `get` & `set`: O(1) 

  * ### String

    >* search_KMP

    >* search_multipatterns

    >  * todo

  * ### Graph

    > * Graph

    > * Dijkstra

    > * topological_traversal

  * ### Common useful functions

    > * `binary_search`

    >   * General binary search, binary_search(sorted_data, from, to, user_func), where user_func(x) defines the data as [False, ..., False, True, ..., True], this function returns the first position of 'True'.

    >   * Many practical problems can be converted to this form, like binary_find, lower_bound, upper_bound, peak position in a rotated sorted array and etc.

    > * `is_none_or_empty`

    > * `histogram_ascii`

    > * `is_sorted` 

    > * `unique` 

    > * `cmp`

    > * `split_data_by_func` 

    > * `eq`

    > * `discrete_sample` 

    > * `group_by_key_fun` 

    > * `top_n`

    > * `clamp`

    > * `argmax`

    > * `argmin`

    > * `make_list`

    > * `swap`

    > * `rotate`

    > * `copy_to`

    > * `kth_smallest_element`

    > * `lower_bound`

    > * `upper_bound`

    > * `reverse_in_place`

    > * `sort_in_place`

    > * `find_first_if`

    > * `find_last_if`

    > * `next_permutation`

    > * `prev_permutation`

    > * `factorial`

    > * `combinatorial_number`

    > * `permutation_number`

    > * `combinations_with_duplicate`

    > * `longest_common_substr`

    > * `top_k_similar`