> ## Documentation Index > Fetch the complete documentation index at: https://leetcode-py.wisl.dev/llms.txt > Use this file to discover all available pages before exploring further. > ## Agent Instructions > leetcode-py is a Python LeetCode practice environment generator with one CLI: lcpy. It is not a service or platform. > Each problem is a directory under leetcode/ with README.md, solution.py, test_solution.py, helpers.py, and playground.ipynb. lcpy gen creates them from JSON templates bundled with the package. > Examples are backed by tests; copy them verbatim. # NeetCode 150 > All 154 NeetCode 150 problems with links to each problem and solution. NeetCode 150 holds 154 problems (28 Easy, 102 Medium, 24 Hard). Generate the whole collection into the current directory: ```bash theme={"theme":{"light":"github-light","dark":"github-dark"}} lcpy gen -t neetcode-150 ``` | # | Problem | Difficulty | Solution | | ---- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------- | ----------------------------------------------------------------------------------------------------------------------------------------------- | | 1 | [Two Sum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/two_sum/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/two_sum/solution.py) | | 2 | [Add Two Numbers](https://github.com/wislertt/leetcode-py/blob/main/leetcode/add_two_numbers/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/add_two_numbers/solution.py) | | 3 | [Longest Substring Without Repeating Characters](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_substring_without_repeating_characters/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_substring_without_repeating_characters/solution.py) | | 4 | [Median of Two Sorted Arrays](https://github.com/wislertt/leetcode-py/blob/main/leetcode/median_of_two_sorted_arrays/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/median_of_two_sorted_arrays/solution.py) | | 5 | [Longest Palindromic Substring](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_palindromic_substring/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_palindromic_substring/solution.py) | | 7 | [Reverse Integer](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_integer/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_integer/solution.py) | | 10 | [Regular Expression Matching](https://github.com/wislertt/leetcode-py/blob/main/leetcode/regular_expression_matching/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/regular_expression_matching/solution.py) | | 11 | [Container With Most Water](https://github.com/wislertt/leetcode-py/blob/main/leetcode/container_with_most_water/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/container_with_most_water/solution.py) | | 15 | [3Sum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/three_sum/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/three_sum/solution.py) | | 17 | [Letter Combinations of a Phone Number](https://github.com/wislertt/leetcode-py/blob/main/leetcode/letter_combinations_of_a_phone_number/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/letter_combinations_of_a_phone_number/solution.py) | | 19 | [Remove Nth Node From End of List](https://github.com/wislertt/leetcode-py/blob/main/leetcode/remove_nth_node_from_end_of_list/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/remove_nth_node_from_end_of_list/solution.py) | | 20 | [Valid Parentheses](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_parentheses/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_parentheses/solution.py) | | 21 | [Merge Two Sorted Lists](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_two_sorted_lists/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_two_sorted_lists/solution.py) | | 22 | [Generate Parentheses](https://github.com/wislertt/leetcode-py/blob/main/leetcode/generate_parentheses/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/generate_parentheses/solution.py) | | 23 | [Merge k Sorted Lists](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_k_sorted_lists/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_k_sorted_lists/solution.py) | | 25 | [Reverse Nodes in k-Group](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_nodes_in_k_group/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_nodes_in_k_group/solution.py) | | 33 | [Search in Rotated Sorted Array](https://github.com/wislertt/leetcode-py/blob/main/leetcode/search_in_rotated_sorted_array/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/search_in_rotated_sorted_array/solution.py) | | 36 | [Valid Sudoku](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_sudoku/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_sudoku/solution.py) | | 39 | [Combination Sum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/combination_sum/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/combination_sum/solution.py) | | 40 | [Combination Sum II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/combination_sum_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/combination_sum_ii/solution.py) | | 42 | [Trapping Rain Water](https://github.com/wislertt/leetcode-py/blob/main/leetcode/trapping_rain_water/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/trapping_rain_water/solution.py) | | 43 | [Multiply Strings](https://github.com/wislertt/leetcode-py/blob/main/leetcode/multiply_strings/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/multiply_strings/solution.py) | | 45 | [Jump Game II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/jump_game_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/jump_game_ii/solution.py) | | 46 | [Permutations](https://github.com/wislertt/leetcode-py/blob/main/leetcode/permutations/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/permutations/solution.py) | | 48 | [Rotate Image](https://github.com/wislertt/leetcode-py/blob/main/leetcode/rotate_image/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/rotate_image/solution.py) | | 49 | [Group Anagrams](https://github.com/wislertt/leetcode-py/blob/main/leetcode/group_anagrams/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/group_anagrams/solution.py) | | 50 | [Pow(x, n)](https://github.com/wislertt/leetcode-py/blob/main/leetcode/powx_n/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/powx_n/solution.py) | | 51 | [N-Queens](https://github.com/wislertt/leetcode-py/blob/main/leetcode/n_queens/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/n_queens/solution.py) | | 53 | [Maximum Subarray](https://github.com/wislertt/leetcode-py/blob/main/leetcode/maximum_subarray/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/maximum_subarray/solution.py) | | 54 | [Spiral Matrix](https://github.com/wislertt/leetcode-py/blob/main/leetcode/spiral_matrix/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/spiral_matrix/solution.py) | | 55 | [Jump Game](https://github.com/wislertt/leetcode-py/blob/main/leetcode/jump_game/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/jump_game/solution.py) | | 56 | [Merge Intervals](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_intervals/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_intervals/solution.py) | | 57 | [Insert Interval](https://github.com/wislertt/leetcode-py/blob/main/leetcode/insert_interval/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/insert_interval/solution.py) | | 62 | [Unique Paths](https://github.com/wislertt/leetcode-py/blob/main/leetcode/unique_paths/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/unique_paths/solution.py) | | 66 | [Plus One](https://github.com/wislertt/leetcode-py/blob/main/leetcode/plus_one/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/plus_one/solution.py) | | 70 | [Climbing Stairs](https://github.com/wislertt/leetcode-py/blob/main/leetcode/climbing_stairs/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/climbing_stairs/solution.py) | | 72 | [Edit Distance](https://github.com/wislertt/leetcode-py/blob/main/leetcode/edit_distance/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/edit_distance/solution.py) | | 73 | [Set Matrix Zeroes](https://github.com/wislertt/leetcode-py/blob/main/leetcode/set_matrix_zeroes/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/set_matrix_zeroes/solution.py) | | 74 | [Search a 2D Matrix](https://github.com/wislertt/leetcode-py/blob/main/leetcode/search_a_2d_matrix/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/search_a_2d_matrix/solution.py) | | 76 | [Minimum Window Substring](https://github.com/wislertt/leetcode-py/blob/main/leetcode/minimum_window_substring/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/minimum_window_substring/solution.py) | | 78 | [Subsets](https://github.com/wislertt/leetcode-py/blob/main/leetcode/subsets/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/subsets/solution.py) | | 79 | [Word Search](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_search/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_search/solution.py) | | 84 | [Largest Rectangle in Histogram](https://github.com/wislertt/leetcode-py/blob/main/leetcode/largest_rectangle_in_histogram/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/largest_rectangle_in_histogram/solution.py) | | 90 | [Subsets II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/subsets_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/subsets_ii/solution.py) | | 91 | [Decode Ways](https://github.com/wislertt/leetcode-py/blob/main/leetcode/decode_ways/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/decode_ways/solution.py) | | 97 | [Interleaving String](https://github.com/wislertt/leetcode-py/blob/main/leetcode/interleaving_string/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/interleaving_string/solution.py) | | 98 | [Validate Binary Search Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/validate_binary_search_tree/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/validate_binary_search_tree/solution.py) | | 100 | [Same Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/same_tree/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/same_tree/solution.py) | | 102 | [Binary Tree Level Order Traversal](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_tree_level_order_traversal/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_tree_level_order_traversal/solution.py) | | 104 | [Maximum Depth of Binary Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/maximum_depth_of_binary_tree/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/maximum_depth_of_binary_tree/solution.py) | | 105 | [Construct Binary Tree from Preorder and Inorder Traversal](https://github.com/wislertt/leetcode-py/blob/main/leetcode/construct_binary_tree_from_preorder_and_inorder_traversal/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/construct_binary_tree_from_preorder_and_inorder_traversal/solution.py) | | 110 | [Balanced Binary Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/balanced_binary_tree/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/balanced_binary_tree/solution.py) | | 115 | [Distinct Subsequences](https://github.com/wislertt/leetcode-py/blob/main/leetcode/distinct_subsequences/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/distinct_subsequences/solution.py) | | 121 | [Best Time to Buy and Sell Stock](https://github.com/wislertt/leetcode-py/blob/main/leetcode/best_time_to_buy_and_sell_stock/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/best_time_to_buy_and_sell_stock/solution.py) | | 124 | [Binary Tree Maximum Path Sum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_tree_maximum_path_sum/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_tree_maximum_path_sum/solution.py) | | 125 | [Valid Palindrome](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_palindrome/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_palindrome/solution.py) | | 127 | [Word Ladder](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_ladder/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_ladder/solution.py) | | 128 | [Longest Consecutive Sequence](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_consecutive_sequence/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_consecutive_sequence/solution.py) | | 130 | [Surrounded Regions](https://github.com/wislertt/leetcode-py/blob/main/leetcode/surrounded_regions/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/surrounded_regions/solution.py) | | 131 | [Palindrome Partitioning](https://github.com/wislertt/leetcode-py/blob/main/leetcode/palindrome_partitioning/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/palindrome_partitioning/solution.py) | | 133 | [Clone Graph](https://github.com/wislertt/leetcode-py/blob/main/leetcode/clone_graph/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/clone_graph/solution.py) | | 134 | [Gas Station](https://github.com/wislertt/leetcode-py/blob/main/leetcode/gas_station/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/gas_station/solution.py) | | 136 | [Single Number](https://github.com/wislertt/leetcode-py/blob/main/leetcode/single_number/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/single_number/solution.py) | | 138 | [Copy List with Random Pointer](https://github.com/wislertt/leetcode-py/blob/main/leetcode/copy_list_with_random_pointer/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/copy_list_with_random_pointer/solution.py) | | 139 | [Word Break](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_break/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_break/solution.py) | | 141 | [Linked List Cycle](https://github.com/wislertt/leetcode-py/blob/main/leetcode/linked_list_cycle/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/linked_list_cycle/solution.py) | | 143 | [Reorder List](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reorder_list/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reorder_list/solution.py) | | 146 | [LRU Cache](https://github.com/wislertt/leetcode-py/blob/main/leetcode/lru_cache/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/lru_cache/solution.py) | | 150 | [Evaluate Reverse Polish Notation](https://github.com/wislertt/leetcode-py/blob/main/leetcode/evaluate_reverse_polish_notation/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/evaluate_reverse_polish_notation/solution.py) | | 152 | [Maximum Product Subarray](https://github.com/wislertt/leetcode-py/blob/main/leetcode/maximum_product_subarray/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/maximum_product_subarray/solution.py) | | 153 | [Find Minimum in Rotated Sorted Array](https://github.com/wislertt/leetcode-py/blob/main/leetcode/find_minimum_in_rotated_sorted_array/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/find_minimum_in_rotated_sorted_array/solution.py) | | 155 | [Min Stack](https://github.com/wislertt/leetcode-py/blob/main/leetcode/min_stack/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/min_stack/solution.py) | | 167 | [Two Sum II - Input Array Is Sorted](https://github.com/wislertt/leetcode-py/blob/main/leetcode/two_sum_ii_input_array_is_sorted/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/two_sum_ii_input_array_is_sorted/solution.py) | | 190 | [Reverse Bits](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_bits/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_bits/solution.py) | | 191 | [Number of 1 Bits](https://github.com/wislertt/leetcode-py/blob/main/leetcode/number_of_1_bits/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/number_of_1_bits/solution.py) | | 198 | [House Robber](https://github.com/wislertt/leetcode-py/blob/main/leetcode/house_robber/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/house_robber/solution.py) | | 199 | [Binary Tree Right Side View](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_tree_right_side_view/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_tree_right_side_view/solution.py) | | 200 | [Number of Islands](https://github.com/wislertt/leetcode-py/blob/main/leetcode/number_of_islands/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/number_of_islands/solution.py) | | 202 | [Happy Number](https://github.com/wislertt/leetcode-py/blob/main/leetcode/happy_number/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/happy_number/solution.py) | | 206 | [Reverse Linked List](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_linked_list/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reverse_linked_list/solution.py) | | 207 | [Course Schedule](https://github.com/wislertt/leetcode-py/blob/main/leetcode/course_schedule/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/course_schedule/solution.py) | | 208 | [Implement Trie (Prefix Tree)](https://github.com/wislertt/leetcode-py/blob/main/leetcode/implement_trie_prefix_tree/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/implement_trie_prefix_tree/solution.py) | | 210 | [Course Schedule II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/course_schedule_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/course_schedule_ii/solution.py) | | 211 | [Design Add and Search Words Data Structure](https://github.com/wislertt/leetcode-py/blob/main/leetcode/design_add_and_search_words_data_structure/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/design_add_and_search_words_data_structure/solution.py) | | 212 | [Word Search II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_search_ii/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/word_search_ii/solution.py) | | 213 | [House Robber II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/house_robber_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/house_robber_ii/solution.py) | | 215 | [Kth Largest Element in an Array](https://github.com/wislertt/leetcode-py/blob/main/leetcode/kth_largest_element_in_an_array/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/kth_largest_element_in_an_array/solution.py) | | 217 | [Contains Duplicate](https://github.com/wislertt/leetcode-py/blob/main/leetcode/contains_duplicate/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/contains_duplicate/solution.py) | | 226 | [Invert Binary Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/invert_binary_tree/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/invert_binary_tree/solution.py) | | 230 | [Kth Smallest Element in a BST](https://github.com/wislertt/leetcode-py/blob/main/leetcode/kth_smallest_element_in_a_bst/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/kth_smallest_element_in_a_bst/solution.py) | | 235 | [Lowest Common Ancestor of a Binary Search Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/lowest_common_ancestor_of_a_binary_search_tree/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/lowest_common_ancestor_of_a_binary_search_tree/solution.py) | | 238 | [Product of Array Except Self](https://github.com/wislertt/leetcode-py/blob/main/leetcode/product_of_array_except_self/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/product_of_array_except_self/solution.py) | | 239 | [Sliding Window Maximum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/sliding_window_maximum/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/sliding_window_maximum/solution.py) | | 242 | [Valid Anagram](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_anagram/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_anagram/solution.py) | | 252 | [Meeting Rooms](https://github.com/wislertt/leetcode-py/blob/main/leetcode/meeting_rooms/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/meeting_rooms/solution.py) | | 253 | [Meeting Rooms II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/meeting_rooms_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/meeting_rooms_ii/solution.py) | | 261 | [Graph Valid Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/graph_valid_tree/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/graph_valid_tree/solution.py) | | 268 | [Missing Number](https://github.com/wislertt/leetcode-py/blob/main/leetcode/missing_number/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/missing_number/solution.py) | | 269 | [Alien Dictionary](https://github.com/wislertt/leetcode-py/blob/main/leetcode/alien_dictionary/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/alien_dictionary/solution.py) | | 271 | [Encode and Decode Strings](https://github.com/wislertt/leetcode-py/blob/main/leetcode/encode_and_decode_strings/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/encode_and_decode_strings/solution.py) | | 286 | [Walls And Gates](https://github.com/wislertt/leetcode-py/blob/main/leetcode/walls_and_gates/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/walls_and_gates/solution.py) | | 287 | [Find the Duplicate Number](https://github.com/wislertt/leetcode-py/blob/main/leetcode/find_the_duplicate_number/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/find_the_duplicate_number/solution.py) | | 295 | [Find Median from Data Stream](https://github.com/wislertt/leetcode-py/blob/main/leetcode/find_median_from_data_stream/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/find_median_from_data_stream/solution.py) | | 297 | [Serialize and Deserialize Binary Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/serialize_and_deserialize_binary_tree/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/serialize_and_deserialize_binary_tree/solution.py) | | 300 | [Longest Increasing Subsequence](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_increasing_subsequence/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_increasing_subsequence/solution.py) | | 309 | [Best Time to Buy and Sell Stock with Cooldown](https://github.com/wislertt/leetcode-py/blob/main/leetcode/best_time_to_buy_and_sell_stock_with_cooldown/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/best_time_to_buy_and_sell_stock_with_cooldown/solution.py) | | 312 | [Burst Balloons](https://github.com/wislertt/leetcode-py/blob/main/leetcode/burst_balloons/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/burst_balloons/solution.py) | | 322 | [Coin Change](https://github.com/wislertt/leetcode-py/blob/main/leetcode/coin_change/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/coin_change/solution.py) | | 323 | [Number of Connected Components in an Undirected Graph](https://github.com/wislertt/leetcode-py/blob/main/leetcode/number_of_connected_components_in_an_undirected_graph/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/number_of_connected_components_in_an_undirected_graph/solution.py) | | 329 | [Longest Increasing Path in a Matrix](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_increasing_path_in_a_matrix/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_increasing_path_in_a_matrix/solution.py) | | 332 | [Reconstruct Itinerary](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reconstruct_itinerary/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/reconstruct_itinerary/solution.py) | | 338 | [Counting Bits](https://github.com/wislertt/leetcode-py/blob/main/leetcode/counting_bits/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/counting_bits/solution.py) | | 347 | [Top K Frequent Elements](https://github.com/wislertt/leetcode-py/blob/main/leetcode/top_k_frequent_elements/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/top_k_frequent_elements/solution.py) | | 355 | [Design Twitter](https://github.com/wislertt/leetcode-py/blob/main/leetcode/design_twitter/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/design_twitter/solution.py) | | 371 | [Sum of Two Integers](https://github.com/wislertt/leetcode-py/blob/main/leetcode/sum_of_two_integers/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/sum_of_two_integers/solution.py) | | 377 | [Combination Sum IV](https://github.com/wislertt/leetcode-py/blob/main/leetcode/combination_sum_iv/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/combination_sum_iv/solution.py) | | 416 | [Partition Equal Subset Sum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/partition_equal_subset_sum/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/partition_equal_subset_sum/solution.py) | | 417 | [Pacific Atlantic Water Flow](https://github.com/wislertt/leetcode-py/blob/main/leetcode/pacific_atlantic_water_flow/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/pacific_atlantic_water_flow/solution.py) | | 424 | [Longest Repeating Character Replacement](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_repeating_character_replacement/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_repeating_character_replacement/solution.py) | | 435 | [Non-overlapping Intervals](https://github.com/wislertt/leetcode-py/blob/main/leetcode/non_overlapping_intervals/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/non_overlapping_intervals/solution.py) | | 494 | [Target Sum](https://github.com/wislertt/leetcode-py/blob/main/leetcode/target_sum/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/target_sum/solution.py) | | 518 | [Coin Change II](https://github.com/wislertt/leetcode-py/blob/main/leetcode/coin_change_ii/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/coin_change_ii/solution.py) | | 528 | [Random Pick with Weight](https://github.com/wislertt/leetcode-py/blob/main/leetcode/random_pick_with_weight/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/random_pick_with_weight/solution.py) | | 543 | [Diameter of Binary Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/diameter_of_binary_tree/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/diameter_of_binary_tree/solution.py) | | 567 | [Permutation in String](https://github.com/wislertt/leetcode-py/blob/main/leetcode/permutation_in_string/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/permutation_in_string/solution.py) | | 572 | [Subtree of Another Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/subtree_of_another_tree/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/subtree_of_another_tree/solution.py) | | 621 | [Task Scheduler](https://github.com/wislertt/leetcode-py/blob/main/leetcode/task_scheduler/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/task_scheduler/solution.py) | | 632 | [Smallest Range Covering Elements from K Lists](https://github.com/wislertt/leetcode-py/blob/main/leetcode/smallest_range_covering_elements_from_k_lists/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/smallest_range_covering_elements_from_k_lists/solution.py) | | 647 | [Palindromic Substrings](https://github.com/wislertt/leetcode-py/blob/main/leetcode/palindromic_substrings/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/palindromic_substrings/solution.py) | | 678 | [Valid Parenthesis String](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_parenthesis_string/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/valid_parenthesis_string/solution.py) | | 684 | [Redundant Connection](https://github.com/wislertt/leetcode-py/blob/main/leetcode/redundant_connection/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/redundant_connection/solution.py) | | 695 | [Max Area of Island](https://github.com/wislertt/leetcode-py/blob/main/leetcode/max_area_of_island/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/max_area_of_island/solution.py) | | 703 | [Kth Largest Element in a Stream](https://github.com/wislertt/leetcode-py/blob/main/leetcode/kth_largest_element_in_a_stream/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/kth_largest_element_in_a_stream/solution.py) | | 704 | [Binary Search](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_search/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/binary_search/solution.py) | | 739 | [Daily Temperatures](https://github.com/wislertt/leetcode-py/blob/main/leetcode/daily_temperatures/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/daily_temperatures/solution.py) | | 743 | [Network Delay Time](https://github.com/wislertt/leetcode-py/blob/main/leetcode/network_delay_time/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/network_delay_time/solution.py) | | 746 | [Min Cost Climbing Stairs](https://github.com/wislertt/leetcode-py/blob/main/leetcode/min_cost_climbing_stairs/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/min_cost_climbing_stairs/solution.py) | | 763 | [Partition Labels](https://github.com/wislertt/leetcode-py/blob/main/leetcode/partition_labels/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/partition_labels/solution.py) | | 778 | [Swim in Rising Water](https://github.com/wislertt/leetcode-py/blob/main/leetcode/swim_in_rising_water/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/swim_in_rising_water/solution.py) | | 787 | [Cheapest Flights Within K Stops](https://github.com/wislertt/leetcode-py/blob/main/leetcode/cheapest_flights_within_k_stops/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/cheapest_flights_within_k_stops/solution.py) | | 815 | [Bus Routes](https://github.com/wislertt/leetcode-py/blob/main/leetcode/bus_routes/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/bus_routes/solution.py) | | 846 | [Hand of Straights](https://github.com/wislertt/leetcode-py/blob/main/leetcode/hand_of_straights/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/hand_of_straights/solution.py) | | 853 | [Car Fleet](https://github.com/wislertt/leetcode-py/blob/main/leetcode/car_fleet/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/car_fleet/solution.py) | | 875 | [Koko Eating Bananas](https://github.com/wislertt/leetcode-py/blob/main/leetcode/koko_eating_bananas/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/koko_eating_bananas/solution.py) | | 973 | [K Closest Points to Origin](https://github.com/wislertt/leetcode-py/blob/main/leetcode/k_closest_points_to_origin/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/k_closest_points_to_origin/solution.py) | | 981 | [Time Based Key-Value Store](https://github.com/wislertt/leetcode-py/blob/main/leetcode/time_based_key_value_store/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/time_based_key_value_store/solution.py) | | 994 | [Rotting Oranges](https://github.com/wislertt/leetcode-py/blob/main/leetcode/rotting_oranges/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/rotting_oranges/solution.py) | | 1046 | [Last Stone Weight](https://github.com/wislertt/leetcode-py/blob/main/leetcode/last_stone_weight/README.md) | Easy | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/last_stone_weight/solution.py) | | 1143 | [Longest Common Subsequence](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_common_subsequence/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/longest_common_subsequence/solution.py) | | 1448 | [Count Good Nodes in Binary Tree](https://github.com/wislertt/leetcode-py/blob/main/leetcode/count_good_nodes_in_binary_tree/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/count_good_nodes_in_binary_tree/solution.py) | | 1584 | [Min Cost to Connect All Points](https://github.com/wislertt/leetcode-py/blob/main/leetcode/min_cost_to_connect_all_points/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/min_cost_to_connect_all_points/solution.py) | | 1851 | [Minimum Interval to Include Each Query](https://github.com/wislertt/leetcode-py/blob/main/leetcode/minimum_interval_to_include_each_query/README.md) | Hard | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/minimum_interval_to_include_each_query/solution.py) | | 1899 | [Merge Triplets to Form Target Triplet](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_triplets_to_form_target_triplet/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/merge_triplets_to_form_target_triplet/solution.py) | | 2013 | [Detect Squares](https://github.com/wislertt/leetcode-py/blob/main/leetcode/detect_squares/README.md) | Medium | [solution.py](https://github.com/wislertt/leetcode-py/blob/main/leetcode/detect_squares/solution.py) |