# leetcode **Repository Path**: geeknonerd/leetcode ## Basic Information - **Project Name**: leetcode - **Description**: 用我的方法解决LeetCode问题；每日更新。 - **Primary Language**: Python - **License**: GPL-3.0 - **Default Branch**: main - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 0 - **Forks**: 0 - **Created**: 2021-08-02 - **Last Updated**: 2022-12-02 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README # [LeetCode](https://leetcode-cn.com/) [![License](https://img.shields.io/badge/license-GPL_3.0-blue.svg)](LICENSE.md) ![Language](https://img.shields.io/badge/language-Python3-blue.svg) If you like this project, please leave me a star. ★ ## Algorithms | # | Title | Solutions | Difficulty | Tag | |------|---------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------|------------|---------------------------------------------------------| | 704 | [binary-search](https://leetcode-cn.com/problems/binary-search) | [Solution](search/binary_search.py) | Easy | Array, Binary Search | | 278 | [first-bad-version](https://leetcode-cn.com/problems/first-bad-version) | [Solution](search/first_bad_version.py) | Easy | Binary Search | | 35 | [search-insert-position](https://leetcode-cn.com/problems/search-insert-position) | [Solution](search/search_insert_position.py) | Easy | Array, Binary Search | | 977 | [squares-of-a-sorted-array](https://leetcode-cn.com/problems/squares-of-a-sorted-array) | [Solution](sort/squares_of_a_sorted_array.py) | Easy | Array, Two Pointers, Sort | | 189 | [rotate-array](https://leetcode-cn.com/problems/rotate-array) | [Solution](rotate/rotate_array.py) | Medium | Array, Two Pointers, Math | | 283 | [move-zeroes](https://leetcode-cn.com/problems/move-zeroes) | [Solution](move/move_zeroes.py) | Easy | Array, Two Pointers | | 167 | [two-sum-ii-input-array-is-sorted](https://leetcode-cn.com/problems/two-sum-ii-input-array-is-sorted) | [Solution](search/two_sum_ii_input_array_is_sorted.py) | Easy | Array, Two Pointers, Binary Search | | 344 | [reverse-string](https://leetcode-cn.com/problems/reverse-string) | [Solution](reverse/reverse_string.py) | Easy | Recursion, Two Pointers, String | | 557 | [reverse-words-in-a-string-iii](https://leetcode-cn.com/problems/reverse-words-in-a-string-iii) | [Solution](reverse/reverse_words_in_a_string_iii.py) | Easy | Two Pointers, String | | 876 | [middle-of-the-linked-list](https://leetcode-cn.com/problems/middle-of-the-linked-list) | [Solution](search/middle_of_the_linked_list.py) | Easy | LinkedList, Two Pointers | | 19 | [remove-nth-node-from-end-of-list](https://leetcode-cn.com/problems/remove-nth-node-from-end-of-list) | [Solution](search/remove_nth_node_from_end_of_list.py) | Medium | LinkedList, Two Pointers | | 3 | [longest-substring-without-repeating-characters](https://leetcode-cn.com/problems/longest-substring-without-repeating-characters) | [Solution](search/longest_substring_without_repeating_characters.py) | Medium | HashTable, String, Sliding Window | | 567 | [permutation-in-string](https://leetcode-cn.com/problems/permutation-in-string) | [Solution](permutation/permutation_in_string.py) | Medium | HashTable, Two Pointers, String | | 733 | [flood-fill](https://leetcode-cn.com/problems/flood-fill) | [Solution](smath/flood_fill.py) | Easy | DFS, BFS, Array | | 695 | [max-area-of-island](https://leetcode-cn.com/problems/max-area-of-island) | [Solution](smath/max_area_of_island.py) | Medium | DFS, BFS | | 617 | [merge-two-binary-trees](https://leetcode-cn.com/problems/merge-two-binary-trees) | [Solution](merge/merge_two_binary_trees.py) | Easy | Tree, DFS, BFS | | 116 | [populating-next-right-pointers-in-each-node](https://leetcode-cn.com/problems/populating-next-right-pointers-in-each-node) | [Solution](populating/populating_next_right_pointers_in_each_node.py) | Medium | Tree, DFS, BFS | | 542 | [01-matrix](https://leetcode-cn.com/problems/01-matrix) | [Solution](smath/01_matrix.py) | Medium | BFS, Array, Dynamic Programming | | 994 | [rotting-oranges](https://leetcode-cn.com/problems/rotting-oranges) | [Solution](smath/rotting_oranges.py) | Medium | BFS, Array, Matrix | | 21 | [merge-two-sorted-lists](https://leetcode-cn.com/problems/merge-two-sorted-lists) | [Solution](merge/merge_two_sorted_lists.py) | Easy | Recursion, LinkedList | | 206 | [reverse-linked-list](https://leetcode-cn.com/problems/reverse-linked-list) | [Solution](reverse/reverse_linked_list.py) | Easy | Recursion, LinkedList | | 77 | [combinations](https://leetcode-cn.com/problems/combinations) | [Solution](combination/combinations.py) | Medium | Array, Backtracking | | 46 | [permutations](https://leetcode-cn.com/problems/permutations) | [Solution](permutation/permutations.py) | Medium | Array, Backtracking | | 784 | [letter-case-permutation](https://leetcode-cn.com/problems/letter-case-permutation) | [Solution](permutation/letter_case_permutation.py) | Medium | Bit Manipulation, String, Backtracking | | 70 | [climbing-stairs](https://leetcode-cn.com/problems/climbing-stairs) | [Solution](smath/climbing_stairs.py) | Easy | Memory Search, Math, Dynamic Programming | | 198 | [house-robber](https://leetcode-cn.com/problems/house-robber) | [Solution](smath/house_robber.py) | Medium | Array, Dynamic Programming | | 120 | [triangle](https://leetcode-cn.com/problems/triangle) | [Solution](smath/triangle.py) | Medium | Array, Dynamic Programming | | 231 | [power-of-two](https://leetcode-cn.com/problems/power-of-two) | [Solution](smath/power_of_two.py) | Easy | Bit Manipulation, Recursion, Math | | 191 | [number-of-1-bits](https://leetcode-cn.com/problems/number-of-1-bits) | [Solution](smath/number_of_1_bits.py) | Easy | Bit Manipulation | | 190 | [reverse-bits](https://leetcode-cn.com/problems/reverse-bits) | [Solution](reverse/reverse_bits.py) | Easy | Bit Manipulation, Divide and Conquer | | 136 | [single-number](https://leetcode-cn.com/problems/single-number) | [Solution](smath/single_number.py) | Easy | Bit Manipulation, Array | | 34 | [find-first-and-last-position-of-element-in-sorted-array](https://leetcode-cn.com/problems/find-first-and-last-position-of-element-in-sorted-array) | [Solution](search/find_first_and_last_position_of_element_in_sorted_array.py) | Medium | Array, Binary Search | | 153 | [find-minimum-in-rotated-sorted-array](https://leetcode-cn.com/problems/find-minimum-in-rotated-sorted-array) | [Solution](search/find_minimum_in_rotated_sorted_array.py) | Medium | Array, Binary Search | | 33 | [search-in-rotated-sorted-array](https://leetcode-cn.com/problems/search-in-rotated-sorted-array) | [Solution](search/search_in_rotated_sorted_array.py) | Medium | Array, Binary Search | | 82 | [remove-duplicates-from-sorted-list-ii](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-list-ii) | [Solution](remove/remove_duplicates_from_sorted_list_ii.py) | Medium | LinkedList, Two Pointers | | 844 | [backspace-string-compare](https://leetcode-cn.com/problems/backspace-string-compare) | [Solution](remove/remove_duplicates_from_sorted_list_ii.py) | Easy | Stack, Two Pointers, String, Simulation | | 986 | [interval-list-intersections](https://leetcode-cn.com/problems/interval-list-intersections) | [Solution](smath/interval_list_intersections.py) | Medium | Array, Two Pointers | | 438 | [find-all-anagrams-in-a-string](https://leetcode-cn.com/problems/find-all-anagrams-in-a-string) | [Solution](search/find_all_anagrams_in_a_string.py) | Medium | Hash Table, String, Sliding Window | | 713 | [subarray-product-less-than-k](https://leetcode-cn.com/problems/subarray-product-less-than-k) | [Solution](smath/subarray_product_less_than_k.py) | Medium | Array, Sliding Window | | 200 | [number-of-islands](https://leetcode-cn.com/problems/number-of-islands) | [Solution](smath/number_of_islands.py) | Medium | DFS, BFS | | 117 | [populating-next-right-pointers-in-each-node-ii](https://leetcode-cn.com/problems/populating-next-right-pointers-in-each-node-ii) | [Solution](populating/populating_next_right_pointers_in_each_node_ii.py) | Medium | Tree, DFS, BFS | | 1091 | [shortest-path-in-binary-matrix](https://leetcode-cn.com/problems/shortest-path-in-binary-matrix) | [Solution](path/shortest_path_in_binary_matrix.py) | Medium | BFS, Array, Matrix | | 78 | [subsets](https://leetcode-cn.com/problems/subsets) | [Solution](smath/subsets.py) | Medium | Bit Manipulation, Array, Backtracking | | 47 | [permutations-ii](https://leetcode-cn.com/problems/permutations-ii) | [Solution](permutation/permutations_ii.py) | Medium | Array, Backtracking | | 17 | [letter-combinations-of-a-phone-number](https://leetcode-cn.com/problems/letter-combinations-of-a-phone-number) | [Solution](combination/letter_combinations_of_a_phone_number.py) | Medium | Hash Table, String, Backtracking | | 213 | [house-robber-ii](https://leetcode-cn.com/problems/house-robber-ii) | [Solution](smath/house_robber_ii.py) | Medium | Array, Dynamic Programming | | 45 | [jump-game-ii](https://leetcode-cn.com/problems/jump-game-ii) | [Solution](smath/jump_game_ii.py) | Medium | Greedy, Array, Dynamic Programming | | 5 | [longest-palindromic-substring](https://leetcode-cn.com/problems/longest-palindromic-substring) | [Solution](search/longest_palindromic_substring.py) | Medium | String, Dynamic Programming | | 91 | [decode-ways](https://leetcode-cn.com/problems/decode-ways) | [Solution](smath/decode_ways.py) | Medium | String, Dynamic Programming | | 300 | [longest-increasing-subsequence](https://leetcode-cn.com/problems/longest-increasing-subsequence) | [Solution](search/longest_increasing_subsequence.py) | Medium | Array, Binary Search, Dynamic Programming | | 1143 | [longest-common-subsequence](https://leetcode-cn.com/problems/longest-common-subsequence) | [Solution](search/longest_common_subsequence.py) | Medium | String, Dynamic Programming | | 322 | [coin-change](https://leetcode-cn.com/problems/coin-change) | [Solution](combination/coin_change.py) | Medium | BFS, Array, Dynamic Programming | | 201 | [bitwise-and-of-numbers-range](https://leetcode-cn.com/problems/bitwise-and-of-numbers-range) | [Solution](smath/bitwise_and_of_numbers_range.py) | Medium | Bit Manipulation | | 384 | [shuffle-an-array](https://leetcode-cn.com/problems/shuffle-an-array) | [Solution](smath/shuffle_an_array.py) | Medium | Array, Math, Randomized | | 130 | [surrounded-regions](https://leetcode-cn.com/problems/surrounded-regions) | [Solution](smath/surrounded_regions.py) | Medium | Array, Math, Randomized | | 74 | [search-a-2d-matrix](https://leetcode-cn.com/problems/search-a-2d-matrix) | [Solution](search/search_a_2d_matrix.py) | Medium | Array, Binary Search, Matrix | | 162 | [find-peak-element](https://leetcode-cn.com/problems/find-peak-element) | [Solution](search/find_peak_element.py) | Medium | Array, Binary Search | | 15 | [3sum](https://leetcode-cn.com/problems/3sum) | [Solution](smath/3sum.py) | Medium | Array, Two Pointers, Sorting | | 11 | [container-with-most-water](https://leetcode-cn.com/problems/container-with-most-water) | [Solution](smath/container_with_most_water.py) | Medium | Greedy, Array, Two Pointers | | 209 | [minimum-size-subarray-sum](https://leetcode-cn.com/problems/minimum-size-subarray-sum) | [Solution](search/minimum_size_subarray_sum.py) | Medium | Array, Binary Search, Prefix Sum | | 547 | [number-of-provinces](https://leetcode-cn.com/problems/number-of-provinces) | [Solution](smath/number_of_provinces.py) | Medium | DFS, BFS | | 572 | [subtree-of-another-tree](https://leetcode-cn.com/problems/subtree-of-another-tree) | [Solution](search/subtree_of_another_tree.py) | Easy | Tree, DFS, Binary Tree | | 797 | [all-paths-from-source-to-target](https://leetcode-cn.com/problems/all-paths-from-source-to-target) | [Solution](search/all_paths_from_source_to_target.py) | Medium | DFS, BFS, Graph | | 90 | [subsets-ii](https://leetcode-cn.com/problems/subsets-ii) | [Solution](smath/subsets_ii.py) | Medium | Bit Manipulation, Array, Backtracking | | 39 | [combination-sum](https://leetcode-cn.com/problems/combination-sum) | [Solution](smath/combination_sum.py) | Medium | Array, Backtracking | | 22 | [generate-parentheses](https://leetcode-cn.com/problems/generate-parentheses) | [Solution](combination/generate_parentheses.py) | Medium | String, Dynamic Programming, Backtracking | | 55 | [jump-game](https://leetcode-cn.com/problems/jump-game) | [Solution](smath/jump_game.py) | Medium | Greedy, Array, Dynamic Programming | | 62 | [unique-paths](https://leetcode-cn.com/problems/unique-paths) | [Solution](path/unique_paths.py) | Medium | Math, Dynamic Programming, Combinatorics | | 40 | [combination-sum-ii](https://leetcode-cn.com/problems/combination-sum-ii) | [Solution](combination/combination_sum_ii.py) | Medium | Array, Backtracking | | 413 | [arithmetic-slices](https://leetcode-cn.com/problems/arithmetic-slices) | [Solution](search/arithmetic_slices.py) | Medium | Array, Backtracking | | 79 | [word-search](https://leetcode-cn.com/problems/word-search) | [Solution](search/word_search.py) | Medium | Array, Backtracking, Matrix | | 139 | [word-break](https://leetcode-cn.com/problems/word-break) | [Solution](search/word_break.py) | Medium | Trie, Memoization, Array, Hash Table | | 673 | [number-of-longest-increasing-subsequence](https://leetcode-cn.com/problems/number-of-longest-increasing-subsequence) | [Solution](search/number_of_longest_increasing_subsequence.py) | Medium | Binary Indexed Tree, Segment Tree, Array | | 583 | [delete-operation-for-two-strings](https://leetcode-cn.com/problems/delete-operation-for-two-strings) | [Solution](smath/delete_operation_for_two_strings.py) | Medium | String, Dynamic Programming | | 343 | [integer-break](https://leetcode-cn.com/problems/integer-break) | [Solution](smath/integer_break.py) | Medium | Math, Dynamic Programming | | 72 | [edit-distance](https://leetcode-cn.com/problems/edit-distance) | [Solution](smath/edit_distance.py) | Hard | String, Dynamic Programming | | 202 | [happy-number](https://leetcode-cn.com/problems/happy-number) | [Solution](smath/happy_number.py) | Easy | Hash Table, Math, Two Pointers | | 149 | [max-points-on-a-line](https://leetcode-cn.com/problems/max-points-on-a-line) | [Solution](smath/max_points_on_a_line.py) | Hard | Geometry, Hash Table, Math | | 217 | [contains-duplicate](https://leetcode-cn.com/problems/contains-duplicate) | [Solution](smath/contains_duplicate.py) | Easy | Array, Hash Table, Sorting | | 1 | [two-sum](https://leetcode-cn.com/problems/two-sum) | [Solution](smath/two_sum.py) | Easy | Array, Hash Table | | 350 | [intersection-of-two-arrays-ii](https://leetcode-cn.com/problems/intersection-of-two-arrays-ii) | [Solution](intersection/intersection_of_two_arrays_ii.py) | Easy | Array, Hash Table, Two Pointers, Binary Search | | 566 | [reshape-the-matrix](https://leetcode-cn.com/problems/reshape-the-matrix) | [Solution](smath/reshape_the_matrix.py) | Easy | Array, Matrix, Simulation | | 36 | [valid-sudoku](https://leetcode-cn.com/problems/valid-sudoku) | [Solution](smath/valid_sudoku.py) | Medium | Array, Hash Table, Matrix | | 387 | [first-unique-character-in-a-string](https://leetcode-cn.com/problems/first-unique-character-in-a-string) | [Solution](search/first_unique_character_in_a_string.py) | Easy | Queue, Hash Table, String, Counting | | 141 | [linked-list-cycle](https://leetcode-cn.com/problems/linked-list-cycle) | [Solution](smath/linked_list_cycle.py) | Easy | Hash Table, LinkedList, Two Pointers | | 83 | [remove-duplicates-from-sorted-list](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-list) | [Solution](smath/remove_duplicates_from_sorted_list.py) | Easy | Hash Table | | 20 | [valid-parentheses](https://leetcode-cn.com/problems/valid-parentheses) | [Solution](smath/valid_parentheses.py) | Easy | Stack, String | | 144 | [binary-tree-preorder-traversal](https://leetcode-cn.com/problems/binary-tree-preorder-traversal) | [Solution](traversal/binary_tree_preorder_traversal.py) | Easy | Stack, Tree, DFS, Binary Tree | | 104 | [maximum-depth-of-binary-tree](https://leetcode-cn.com/problems/maximum-depth-of-binary-tree) | [Solution](smath/maximum_depth_of_binary_tree.py) | Easy | Tree, DFS, BFS | | 101 | [symmetric-tree](https://leetcode-cn.com/problems/symmetric-tree) | [Solution](smath/symmetric_tree.py) | Easy | Tree, DFS, BFS | | 226 | [invert-binary-tree](https://leetcode-cn.com/problems/invert-binary-tree) | [Solution](smath/invert_binary_tree.py) | Easy | Tree, DFS, BFS | | 700 | [search-in-a-binary-search-tree](https://leetcode-cn.com/problems/search-in-a-binary-search-tree) | [Solution](search/search_in_a_binary_search_tree.py) | Easy | Tree, Binary Search Tree, Binary Tree | | 383 | [ransom-note](https://leetcode-cn.com/problems/ransom-note) | [Solution](search/ransom_note.py) | Easy | Hash Table, String, Counting | | 94 | [binary-tree-inorder-traversal](https://leetcode-cn.com/problems/binary-tree-inorder-traversal) | [Solution](search/binary_tree_inorder_traversal.py) | Easy | Stack, Tree, DFS, Binary Tree | | 53 | [maximum-subarray](https://leetcode-cn.com/problems/maximum-subarray) | [Solution](smath/maximum_subarray.py) | Easy | Array, Divide And Conquer, Dynamic Programming | | 88 | [merge-sorted-array](https://leetcode-cn.com/problems/merge-sorted-array) | [Solution](merge/merge_sorted_array.py) | Easy | Array, Two Pointers, Sorting | | 121 | [best-time-to-buy-and-sell-stock](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock) | [Solution](smath/best_time_to_buy_and_sell_stock.py) | Easy | Array, Dynamic Programming | | 118 | [pascals-triangle](https://leetcode-cn.com/problems/pascals-triangle) | [Solution](smath/pascals_triangle.py) | Easy | Array, Dynamic Programming | | 73 | [set-matrix-zeroes](https://leetcode-cn.com/problems/set-matrix-zeroes) | [Solution](smath/set_matrix_zeroes.py) | Medium | Array, Hash Table, Matrix | | 242 | [valid-anagram](https://leetcode-cn.com/problems/valid-anagram) | [Solution](smath/valid_anagram.py) | Easy | Hash Table, String, Sorting | | 203 | [remove-linked-list-elements](https://leetcode-cn.com/problems/remove-linked-list-elements) | [Solution](remove/remove_linked_list_elements.py) | Easy | Recursion, LinkedList | | 232 | [implement-queue-using-stacks](https://leetcode-cn.com/problems/implement-queue-using-stacks) | [Solution](implement/implement_queue_using_stacks.py) | Easy | Stack, Design, Queue | | 145 | [binary-tree-postorder-traversal](https://leetcode-cn.com/problems/binary-tree-postorder-traversal) | [Solution](implement/binary_tree_postorder_traversal.py) | Easy | Stack, Tree, DFS, Binary Tree | | 102 | [binary-tree-level-order-traversal](https://leetcode-cn.com/problems/binary-tree-level-order-traversal) | [Solution](implement/binary_tree_level_order_traversal.py) | Medium | Tree, BFS, Binary Tree | | 112 | [path-sum](https://leetcode-cn.com/problems/path-sum) | [Solution](search/path_sum.py) | Easy | Tree, DFS, Binary Tree | | 701 | [insert-into-a-binary-search-tree](https://leetcode-cn.com/problems/insert-into-a-binary-search-tree) | [Solution](implement/insert_into_a_binary_search_tree.py) | Medium | Tree, Binary Search Tree, Binary Tree | | 653 | [two-sum-iv-input-is-a-bst](https://leetcode-cn.com/problems/two-sum-iv-input-is-a-bst) | [Solution](search/two_sum_iv_input_is_a_bst.py) | Easy | Tree, DFS, BFS | | 235 | [lowest-common-ancestor-of-a-binary-search-tree](https://leetcode-cn.com/problems/lowest-common-ancestor-of-a-binary-search-tree) | [Solution](search/lowest_common_ancestor_of_a_binary_search_tree.py) | Easy | Tree, DFS, BFS | | 98 | [validate-binary-search-tree](https://leetcode-cn.com/problems/validate-binary-search-tree) | [Solution](search/validate_binary_search_tree.py) | Medium | Tree, DFS, BFS, Binary Search Tree | | 169 | [majority-element](https://leetcode-cn.com/problems/majority-element) | [Solution](search/majority_element.py) | Easy | Array, Hash Table, Divide and Conquer, Counting | | 75 | [sort-colors](https://leetcode-cn.com/problems/sort-colors) | [Solution](sort/sort_colors.py) | Medium | Array, Two Pointers, Sorting | | 119 | [pascals-triangle-ii](https://leetcode-cn.com/problems/pascals-triangle-ii) | [Solution](smath/pascals_triangle_ii.py) | Easy | Array, Dynamic Programming | | 240 | [search-a-2d-matrix-ii](https://leetcode-cn.com/problems/search-a-2d-matrix-ii) | [Solution](search/search_a_2d_matrix_ii.py) | Medium | Array, Binary Search, Divide and Conquer, Matrix | | 238 | [product-of-array-except-self](https://leetcode-cn.com/problems/product-of-array-except-self) | [Solution](smath/product_of_array_except_self.py) | Medium | Array, Prefix Sum | | 415 | [add-strings](https://leetcode-cn.com/problems/add-strings) | [Solution](add/add_strings.py) | Easy | Math, String, Simulation | | 290 | [word-pattern](https://leetcode-cn.com/problems/word-pattern) | [Solution](pattern/word_pattern.py) | Easy | Hash Table, String | | 43 | [multiply-strings](https://leetcode-cn.com/problems/multiply-strings) | [Solution](multiply/multiply_strings.py) | Medium | Math, String, Simulation | | 706 | [design-hashmap](https://leetcode-cn.com/problems/design-hashmap) | [Solution](design/design_hashmap.py) | Easy | Design, Array, Hash Table, Linked List | | 2 | [add-two-numbers](https://leetcode-cn.com/problems/add-two-numbers) | [Solution](add/add_two_numbers.py) | Medium | Recursion, Linked List, Math | | 160 | [intersection-of-two-linked-lists](https://leetcode-cn.com/problems/intersection-of-two-linked-lists) | [Solution](intersection/intersection_of_two_linked_lists.py) | Easy | Hash Table, Linked List, Two Pointers | | 707 | [design-linked-list](https://leetcode-cn.com/problems/design-linked-list) | [Solution](design/design_linked_list.py) | Medium | Design, Linked List | | 143 | [reorder-list](https://leetcode-cn.com/problems/reorder-list) | [Solution](sort/reorder_list.py) | Medium | Stack, Recursion, Linked List, Two Pointers | | 155 | [min-stack](https://leetcode-cn.com/problems/min-stack) | [Solution](design/min_stack.py) | Easy | Stack, Design | | 108 | [convert-sorted-array-to-binary-search-tree](https://leetcode-cn.com/problems/convert-sorted-array-to-binary-search-tree) | [Solution](convert/convert_sorted_array_to_binary_search_tree.py) | Easy | Tree, Binary Search Tree, Array, Divide and Conquer | | 113 | [path-sum-ii](https://leetcode-cn.com/problems/path-sum-ii) | [Solution](path/path_sum_ii.py) | Medium | Tree, DFS, Backtracking, Binary Tree | | 230 | [kth-smallest-element-in-a-bst](https://leetcode-cn.com/problems/kth-smallest-element-in-a-bst) | [Solution](search/kth_smallest_element_in_a_bst.py) | Medium | Tree, DFS, Binary Search Tree | | 236 | [lowest-common-ancestor-of-a-binary-tree](https://leetcode-cn.com/problems/lowest-common-ancestor-of-a-binary-tree) | [Solution](smath/lowest_common_ancestor_of_a_binary_tree.py) | Medium | Tree, DFS, Binary Tree | | 997 | [find-the-town-judge](https://leetcode-cn.com/problems/find-the-town-judge) | [Solution](search/find_the_town_judge.py) | Easy | Graph, Array, Hash Table | | 215 | [kth-largest-element-in-an-array](https://leetcode-cn.com/problems/kth-largest-element-in-an-array) | [Solution](search/kth_largest_element_in_an_array.py) | Medium | Array, Divide and Conquer, Quickselect, Sorting | | 164 | [maximum-gap](https://leetcode-cn.com/problems/maximum-gap) | [Solution](search/maximum_gap.py) | Hard | Array, Bucket Sort, Radix Sort, Sorting | | 56 | [merge-intervals](https://leetcode-cn.com/problems/merge-intervals) | [Solution](merge/merge_intervals.py) | Medium | Array, Bucket Sorting | | 48 | [rotate-image](https://leetcode-cn.com/problems/rotate-image) | [Solution](rotate/rotate_image.py) | Medium | Array, Math, Matrix | | 59 | [spiral-matrix-ii](https://leetcode-cn.com/problems/spiral-matrix-ii) | [Solution](rotate/spiral_matrix_ii.py) | Medium | Array, Math, Matrix | | 435 | [non-overlapping-intervals](https://leetcode-cn.com/problems/non-overlapping-intervals) | [Solution](smath/non_overlapping_intervals.py) | Medium | Greedy, Array, Dynamic Programming, Sorting | | 334 | [increasing-triplet-subsequence](https://leetcode-cn.com/problems/increasing-triplet-subsequence) | [Solution](increasing/increasing_triplet_subsequence.py) | Medium | Greedy, Array | | 409 | [longest-palindrome](https://leetcode-cn.com/problems/longest-palindrome) | [Solution](smath/longest_palindrome.py) | Easy | Greedy, Hash Table, String | | 763 | [partition-labels](https://leetcode-cn.com/problems/partition-labels) | [Solution](partition/partition_labels.py) | Medium | Greedy, Hash Table, Two Pointers, String | | 49 | [group-anagrams](https://leetcode-cn.com/problems/group-anagrams) | [Solution](partition/group_anagrams.py) | Medium | Hash Table, String, Sorting | | 560 | [subarray-sum-equals-k](https://leetcode-cn.com/problems/subarray-sum-equals-k) | [Solution](search/subarray_sum_equals_k.py) | Medium | Array, Hash Table, Prefix Sum | | 187 | [repeated-dna-sequences](https://leetcode-cn.com/problems/repeated-dna-sequences) | [Solution](search/repeated_dna_sequences.py) | Medium | Bit Manipulation, Hash Table, String | | 142 | [linked-list-cycle-ii](https://leetcode-cn.com/problems/linked-list-cycle-ii) | [Solution](search/linked_list_cycle_ii.py) | Medium | Hash Table, Linked List, Two Pointers | | 1249 | [minimum-remove-to-make-valid-parentheses](https://leetcode-cn.com/problems/minimum-remove-to-make-valid-parentheses) | [Solution](remove/minimum_remove_to_make_valid_parentheses.py) | Medium | Stack, String | | 24 | [swap-nodes-in-pairs](https://leetcode-cn.com/problems/swap-nodes-in-pairs) | [Solution](swap/swap_nodes_in_pairs.py) | Medium | Recursion, Linked List | | 1823 | [find-the-winner-of-the-circular-game](https://leetcode-cn.com/problems/find-the-winner-of-the-circular-game) | [Solution](search/find_the_winner_of_the_circular_game.py) | Medium | Recursion, Array, Math, Simulation | | 105 | [construct-binary-tree-from-preorder-and-inorder-traversal](https://leetcode-cn.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal) | [Solution](smath/construct_binary_tree_from_preorder_and_inorder_traversal.py) | Medium | Tree, Array, Hash Table, Divide and Conquer | | 199 | [binary-tree-right-side-view](https://leetcode-cn.com/problems/binary-tree-right-side-view) | [Solution](smath/binary_tree_right_side_view.py) | Medium | Tree, DFS, BFS | | 25 | [reverse-nodes-in-k-group](https://leetcode-cn.com/problems/reverse-nodes-in-k-group) | [Solution](reverse/reverse_nodes_in_k_group.py) | Hard | Recursion, Linked List | | 173 | [binary-search-tree-iterator](https://leetcode-cn.com/problems/binary-search-tree-iterator) | [Solution](search/binary_search_tree_iterator.py) | Medium | Stack, Tree, Design, Binary Search Tree | | 297 | [serialize-and-deserialize-binary-tree](https://leetcode-cn.com/problems/serialize-and-deserialize-binary-tree) | [Solution](convert/serialize_and_deserialize_binary_tree.py) | Hard | Tree, DFS, BFS | | 103 | [binary-tree-zigzag-level-order-traversal](https://leetcode-cn.com/problems/binary-tree-zigzag-level-order-traversal) | [Solution](traversal/binary_tree_zigzag_level_order_traversal.py) | Medium | Tree, BFS, Binary Tree | | 1557 | [minimum-number-of-vertices-to-reach-all-nodes](https://leetcode-cn.com/problems/minimum-number-of-vertices-to-reach-all-nodes) | [Solution](traversal/minimum_number_of_vertices_to_reach_all_nodes.py) | Medium | Graph | | 451 | [sort-characters-by-frequency](https://leetcode-cn.com/problems/sort-characters-by-frequency) | [Solution](sort/sort_characters_by_frequency.py) | Medium | Hash Table, String, Bucket Sort, Counting | | 973 | [k-closest-points-to-origin](https://leetcode-cn.com/problems/k-closest-points-to-origin) | [Solution](search/k_closest_points_to_origin.py) | Medium | Hash Table, String, Bucket Sort, Counting | | 347 | [top-k-frequent-elements](https://leetcode-cn.com/problems/top-k-frequent-elements) | [Solution](search/top_k_frequent_elements.py) | Medium | Array, Hash Table, Divide and Conquer, Bucket Sort | | 841 | [keys-and-rooms](https://leetcode-cn.com/problems/keys-and-rooms) | [Solution](smath/keys_and_rooms.py) | Medium | DFS, BFS, Graph | | 509 | [fibonacci-number](https://leetcode-cn.com/problems/fibonacci-number) | [Solution](smath/fibonacci_number.py) | Easy | Recursion, Memoization, Math | | 746 | [min-cost-climbing-stairs](https://leetcode-cn.com/problems/min-cost-climbing-stairs) | [Solution](smath/min_cost_climbing_stairs.py) | Easy | Array, Dynamic Programming | | 918 | [maximum-sum-circular-subarray](https://leetcode-cn.com/problems/maximum-sum-circular-subarray) | [Solution](add/maximum_sum_circular_subarray.py) | Medium | Queue, Array, Divide and Conquer, Dynamic Programming | | 152 | [maximum-product-subarray](https://leetcode-cn.com/problems/maximum-product-subarray) | [Solution](product/maximum_product_subarray.py) | Medium | Array, Dynamic Programming | | 1014 | [best-sightseeing-pair](https://leetcode-cn.com/problems/best-sightseeing-pair) | [Solution](best/best_sightseeing_pair.py) | Medium | Array, Dynamic Programming | | 309 | [best-time-to-buy-and-sell-stock-with-cooldown](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-with-cooldown) | [Solution](best/best_time_to_buy_and_sell_stock_with_cooldown.py) | Medium | Array, Dynamic Programming | | 450 | [delete-node-in-a-bst](https://leetcode-cn.com/problems/delete-node-in-a-bst) | [Solution](search/delete_node_in_a_bst.py) | Medium | Tree, Binary Search Tree, Binary Tree | | 264 | [ugly-number-ii](https://leetcode-cn.com/problems/ugly-number-ii) | [Solution](smath/ugly_number_ii.py) | Medium | Hash Table, Math, Dynamic Programming | | 931 | [minimum-falling-path-sum](https://leetcode-cn.com/problems/minimum-falling-path-sum) | [Solution](path/minimum_falling_path_sum.py) | Medium | Array, Dynamic Programming, Matrix | | 64 | [minimum-path-sum](https://leetcode-cn.com/problems/minimum-path-sum) | [Solution](path/minimum_path_sum.py) | Medium | Array, Dynamic Programming, Matrix | | 1314 | [matrix-block-sum](https://leetcode-cn.com/problems/matrix-block-sum) | [Solution](matrix/matrix_block_sum.py) | Medium | Array, Matrix, Prefix Sum | | 392 | [is-subsequence](https://leetcode-cn.com/problems/is-subsequence) | [Solution](subseq/is_subsequence.py) | Easy | Two Pointers, String, Dynamic Programming | | 42 | [trapping-rain-water](https://leetcode-cn.com/problems/trapping-rain-water) | [Solution](smath/trapping_rain_water.py) | Hard | Stack, Array, Two Pointers, Dynamic Programming | | 377 | [combination-sum-iv](https://leetcode-cn.com/problems/combination-sum-iv) | [Solution](combination/combination_sum_iv.py) | Medium | Array, Dynamic Programming | | 1137 | [n-th-tribonacci-number](https://leetcode-cn.com/problems/n-th-tribonacci-number) | [Solution](search/n_th_tribonacci_number.py) | Easy | Memoization, Math, Dynamic Programming | | 740 | [delete-and-earn](https://leetcode-cn.com/problems/delete-and-earn) | [Solution](remove/delete_and_earn.py) | Medium | Array, Hash Table, Dynamic Programming | | 1567 | [maximum-length-of-subarray-with-positive-product](https://leetcode-cn.com/problems/maximum-length-of-subarray-with-positive-product) | [Solution](product/maximum_length_of_subarray_with_positive_product.py) | Medium | Greedy, Array, Dynamic Programming | | 122 | [best-time-to-buy-and-sell-stock-ii](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-ii) | [Solution](best/best_time_to_buy_and_sell_stock_ii.py) | Medium | Greedy, Array, Dynamic Programming | | 714 | [best-time-to-buy-and-sell-stock-with-transaction-fee](https://leetcode-cn.com/problems/best-time-to-buy-and-sell-stock-with-transaction-fee) | [Solution](best/best_time_to_buy_and_sell_stock_with_transaction_fee.py) | Medium | Greedy, Array, Dynamic Programming | | 96 | [unique-binary-search-trees](https://leetcode-cn.com/problems/unique-binary-search-trees) | [Solution](search/unique_binary_search_trees.py) | Medium | Tree, Binary Search Tree, Math, Dynamic Programming | | 304 | [range-sum-query-2d-immutable](https://leetcode-cn.com/problems/range-sum-query-2d-immutable) | [Solution](search/range_sum_query_2d_immutable.py) | Medium | Design, Array, Matrix, Prefix Sum | | 63 | [unique-paths-ii](https://leetcode-cn.com/problems/unique-paths-ii) | [Solution](path/unique_paths_ii.py) | Medium | Array, Dynamic Programming, Matrix | | 221 | [maximal-square](https://leetcode-cn.com/problems/maximal-square) | [Solution](smath/maximal_square.py) | Medium | Array, Dynamic Programming, Matrix | | 516 | [longest-palindromic-subsequence](https://leetcode-cn.com/problems/longest-palindromic-subsequence) | [Solution](subseq/longest_palindromic_subsequence.py) | Medium | String, Dynamic Programming | | 518 | [coin-change-2](https://leetcode-cn.com/problems/coin-change-2) | [Solution](subseq/coin_change_2.py) | Medium | Array, Dynamic Programming | | 9 | [palindrome-number](https://leetcode-cn.com/problems/palindrome-number/) | [Python](smath/palindrome_number.py),[Go](go/math/palindrome_number.go) | Easy | Math | | 13 | [roman-to-integer](https://leetcode-cn.com/problems/roman-to-integer/) | [Python](smath/roman_to_integer.py),[Go](go/math/roman_to_integer.go) | Easy | Hash Table, Math, String | | 14 | [longest-common-prefix](https://leetcode-cn.com/problems/longest-common-prefix/) | [Python](search/longest_common_prefix.py),[Go](go/search/longest_common_prefix.go) | Easy | String | | 26 | [remove-duplicates-from-sorted-array](https://leetcode-cn.com/problems/remove-duplicates-from-sorted-array/) | [Python](search/remove_duplicates_from_sorted_array.py),[Go](go/search/remove_duplicates_from_sorted_array.go) | Easy | Array, Two Pointers | | 27 | [remove-element](https://leetcode-cn.com/problems/remove-element/) | [Python](search/remove_element.py),[Go](go/search/remove_element.go) | Easy | Array, Two Pointers | | 28 | [implement-strstr](https://leetcode-cn.com/problems/implement-strstr/) | [Python](search/implement_strstr.py),[Go](go/search/implement_strstr.go) | Easy | Two Pointers, String, String Matching | | 58 | [length-of-last-word](https://leetcode-cn.com/problems/length-of-last-word/) | [Python](smath/length_of_last_word.py),[Go](go/math/length_of_last_word.go) | Easy | String | | 66 | [plus-one](https://leetcode-cn.com/problems/plus-one/) | [Python](smath/plus_one.py),[Go](go/math/plus_one.go) | Easy | Array, Math | | 67 | [add-binary](https://leetcode-cn.com/problems/add-binary/) | [Python](smath/add_binary.py),[Go](go/math/add_binary.go) | Easy | Bit Manipulation, Math, String, Simulation | | 69 | [sqrtx](https://leetcode-cn.com/problems/sqrtx/) | [Python](smath/sqrtx.py),[Go](go/math/sqrtx.go) | Easy | Math, Binary Search | | 100 | [same-tree](https://leetcode-cn.com/problems/same-tree/) | [Python](search/same_tree.py),[Go](go/search/same_tree.go) | Easy | Tree, DFS, BFS, Binary Tree | | 110 | [balanced-binary-tree](https://leetcode-cn.com/problems/balanced-binary-tree/) | [Python](smath/balanced_binary_tree.py),[Go](go/math/balanced_binary_tree.go) | Easy | Tree, DFS, Binary Tree | | 111 | [minimum-depth-of-binary-tree](https://leetcode-cn.com/problems/minimum-depth-of-binary-tree/) | [Python](smath/minimum_depth_of_binary_tree.py),[Go](go/math/minimum_depth_of_binary_tree.go) | Easy | Tree, DFS, BFS, Binary Tree | | 125 | [valid-palindrome](https://leetcode-cn.com/problems/valid-palindrome/) | [Python](valid/valid_palindrome.py),[Go](go/valid/valid_palindrome.go) | Easy | Two Pointers, String | | 168 | [excel-sheet-column-title](https://leetcode-cn.com/problems/excel-sheet-column-title/) | [Python](smath/excel_sheet_column_title.py),[Go](go/math/excel_sheet_column_title.go) | Easy | Math, String | | 171 | [excel-sheet-column-number](https://leetcode-cn.com/problems/excel-sheet-column-number/) | [Python](smath/excel_sheet_column_number.py),[Go](go/math/excel_sheet_column_number.go) | Easy | Math, String | | 175 | [combine-two-tables](https://leetcode-cn.com/problems/combine-two-tables/) | [SQL](db/combine_two_tables.sql) | Easy | Database | | 205 | [isomorphic-strings](https://leetcode-cn.com/problems/isomorphic-strings/) | [Python](smath/isomorphic_strings.py),[Go](go/math/isomorphic_strings.go) | Easy | Hash Table, String | | 219 | [contains-duplicate-ii](https://leetcode-cn.com/problems/contains-duplicate-ii/) | [Python](search/contains_duplicate_ii.py),[Go](go/search/contains_duplicate_ii.go) | Easy | Array, Hash Table, Sliding Window | | 225 | [implement-stack-using-queues](https://leetcode-cn.com/problems/implement-stack-using-queues/) | [Python](implement/implement_stack_using_queues.py),[Go](go/implement/implement_stack_using_queues.go) | Easy | Stack, Design, Queue | | 228 | [summary-ranges](https://leetcode-cn.com/problems/summary-ranges/) | [Python](search/summary_ranges.py),[Go](go/search/summary_ranges.go) | Easy | Array | | 234 | [palindrome-linked-list](https://leetcode-cn.com/problems/palindrome-linked-list/) | [Python](search/palindrome_linked_list.py),[Go](go/search/palindrome_linked_list.go) | Easy | Stack, Recursion, Linked List, Two Pointers | | 237 | [delete-node-in-a-linked-list](https://leetcode-cn.com/problems/delete-node-in-a-linked-list/) | [Python](search/delete_node_in_a_linked_list.py),[Go](go/search/delete_node_in_a_linked_list.go) | Easy | Linked List | | 257 | [binary-tree-paths](https://leetcode-cn.com/problems/binary-tree-paths/) | [Python](path/binary_tree_paths.py),[Go](go/path/binary_tree_paths.go) | Easy | Tree, DFS, String, Backtracking, Binary Tree | | 258 | [add-digits](https://leetcode-cn.com/problems/add-digits/) | [Python](add/add_digits.py),[Go](go/add/add_digits.go) | Easy | Match, Number Theory, Simulation | | 263 | [ugly-number](https://leetcode-cn.com/problems/ugly-number/) | [Python](smath/ugly_number.py),[Go](go/math/ugly_number.go) | Easy | Math | | 268 | [missing-number](https://leetcode-cn.com/problems/missing-number/) | [Python](smath/missing_number.py),[Go](go/math/missing_number.go) | Easy | Bit Manipulation, Array, Hash Table, Math, Sorting | | 292 | [nim-game](https://leetcode-cn.com/problems/nim-game/) | [Python](smath/nim_game.py),[Go](go/math/nim_game.go) | Easy | Brainteaser, Math, Game Theory | | 303 | [range-sum-query-immutable](https://leetcode-cn.com/problems/range-sum-query-immutable/) | [Python](design/range_sum_query_immutable.py),[Go](go/design/range_sum_query_immutable.go) | Easy | Design, Array, Prefix Sum | | 326 | [power-of-three](https://leetcode-cn.com/problems/power-of-three/) | [Python](smath/power_of_three.py),[Go](go/math/power_of_three.go) | Easy | Recursion, Math | | 338 | [counting-bits](https://leetcode-cn.com/problems/counting-bits/) | [Python](smath/counting_bits.py),[Go](go/math/counting_bits.go) | Easy | Bit Manipulation, Dynamic Programming | | 342 | [power-of-four](https://leetcode-cn.com/problems/power-of-four/) | [Python](smath/power_of_four.py),[Go](go/math/power_of_four.go) | Easy | Bit Manipulation, Recursion, Math | | 345 | [reverse-vowels-of-a-string](https://leetcode-cn.com/problems/reverse-vowels-of-a-string/) | [Python](reverse/reverse_vowels_of_a_string.py),[Go](go/reverse/reverse_vowels_of_a_string.go) | Easy | Two Pointers, String | | 349 | [intersection-of-two-arrays](https://leetcode-cn.com/problems/intersection-of-two-arrays/) | [Python](intersection/intersection_of_two_arrays.py),[Go](go/intersection/intersection_of_two_arrays.go) | Easy | Array, Hash Table, Two Pointers, Binary Search, Sorting | | 367 | [valid-perfect-square](https://leetcode-cn.com/problems/valid-perfect-square/) | [Python](valid/valid_perfect_square.py),[Go](go/valid/valid_perfect_square.go) | Easy | Math, Binary Search | | 374 | [guess-number-higher-or-lower](https://leetcode-cn.com/problems/guess-number-higher-or-lower/) | [Python](guess/guess_number_higher_or_lower.py),[Go](go/guess/guess_number_higher_or_lower.go) | Easy | Binary Search, interactive | | 389 | [find-the-difference](https://leetcode-cn.com/problems/find-the-difference/) | [Python](find/find_the_difference.py),[Go](go/find/find_the_difference.go) | Easy | Bit Manipulation, Hash Table, String, Sorting | | 401 | [binary-watch](https://leetcode-cn.com/problems/binary-watch/) | [Python](smath/binary_watch.py),[Go](go/math/binary_watch.go) | Easy | Bit Manipulation, Backtracking | | 404 | [sum-of-left-leaves](https://leetcode-cn.com/problems/sum-of-left-leaves/) | [Python](smath/sum_of_left_leaves.py),[Go](go/math/sum_of_left_leaves.go) | Easy | Tree, DFS, BFS, Binary Tree | | 405 | [convert-a-number-to-hexadecimal](https://leetcode-cn.com/problems/convert-a-number-to-hexadecimal/) | [Python](smath/convert_a_number_to_hexadecimal.py),[Go](go/math/convert_a_number_to_hexadecimal.go) | Easy | Bit Manipulation, Math | | 412 | [fizz-buzz](https://leetcode-cn.com/problems/fizz-buzz/) | [Python](smath/fizz_buzz.py), [Go](go/math/fizz_buzz.go) | Easy | Math, String, Simulation | | 414 | [third-maximum-number](https://leetcode-cn.com/problems/third-maximum-number/) | [Python](sort/third_maximum_number.py),[Go](go/sort/third_maximum_number/third_maximum_number.go) | Easy | Array, Sorting | | 434 | [number-of-segments-in-a-string](https://leetcode-cn.com/problems/number-of-segments-in-a-string/) | [Python](add/number_of_segments_in_a_string.py),[Go](go/add/number_of_segments_in_a_string.go) | Easy | String | | 441 | [arranging-coins](https://leetcode-cn.com/problems/arranging-coins/) | [Python](search/arranging_coins.py), [Go](go/search/arranging_coins.go) | Easy | Math, Binary Search | | 448 | [find-all-numbers-disappeared-in-an-array](https://leetcode-cn.com/problems/find-all-numbers-disappeared-in-an-array/) | [Python](find/find_all_numbers_disappeared_in_an_array.py),[Go](go/find/find_all_numbers_disappeared_in_an_array.go) | Easy | Array, Hash Table | | 453 | [minimum-moves-to-equal-array-elements](https://leetcode-cn.com/problems/minimum-moves-to-equal-array-elements/) | [Python](move/minimum_moves_to_equal_array_elements.py),[Go](go/move/minimum_moves_to_equal_array_elements.go) | Easy | Array, Math | | 455 | [assign-cookies](https://leetcode-cn.com/problems/assign-cookies/) | [Python](sort/assign_cookies.py),[Go](go/sort/assign_cookies.go) | Easy | Greedy, Array, Sorting | | 459 | [repeated-substring-pattern](https://leetcode-cn.com/problems/repeated-substring-pattern/) | [Python](match/repeated_substring_pattern.py),[Go](go/match/repeated_substring_pattern.go) | Easy | String, String Matching | | 461 | [hamming-distance](https://leetcode-cn.com/problems/hamming-distance/) | [Python](smath/hamming_distance.py),[Go](go/math/hamming_distance.go) | Easy | Bit Manipulation | | 463 | [island-perimeter](https://leetcode-cn.com/problems/island-perimeter/) | [Python](smath/island_perimeter.py),[Go](go/math/island_perimeter.go) | Easy | DFS, BFS, Array, Matrix | | 476 | [number-complement](https://leetcode-cn.com/problems/number-complement/) | [Python](bit/number_complement.py),[Go](go/bit/number_complement.go) | Easy | Bit Manipulation | | 482 | [license-key-formatting](https://leetcode-cn.com/problems/license-key-formatting/) | [Python](convert/license_key_formatting.py),[Go](go/convert/license_key_formatting.go) | Easy | String | | 485 | [max-consecutive-ones](https://leetcode-cn.com/problems/max-consecutive-ones/) | [Python](smath/max_consecutive_ones.py),[Go](go/math/max_consecutive_ones.go) | Easy | Array | | 496 | [next-greater-element-i](https://leetcode-cn.com/problems/next-greater-element-i/) | [Python](traversal/next_greater_element_i.py),[Go](go/traversal/next_greater_element_i.go) | Easy | Stack, Array, Hash Table, Monotonic Stack | | 492 | [construct-the-rectangle](https://leetcode-cn.com/problems/construct-the-rectangle/) | [Python](smath/construct_the_rectangle.py),[Go](go/math/construct_the_rectangle.go) | Easy | Math | | 495 | [teemo-attacking](https://leetcode-cn.com/problems/teemo-attacking/) | [Python](smath/teemo_attacking.py),[Go](go/math/teemo_attacking.go) | Easy | Array, Simulation | | 500 | [keyboard-row](https://leetcode-cn.com/problems/keyboard-row/) | [Go](go/contain/keyboard_row.go) | Easy | Array, Hash Table, String | | 501 | [find-mode-in-binary-search-tree](https://leetcode-cn.com/problems/find-mode-in-binary-search-tree/) | [Python](traversal/find_mode_in_binary_search_tree.py),[Go](go/traversal/find_mode_in_binary_search_tree.go) | Easy | Tree, DFS, Binary Search Tree, Binary Tree | ## Thanks [![PyCharm](resource/pycharm.svg)](https://www.jetbrains.com/)