Leetcode solutions in C++, Java, Python

| Number | Title | Difficulty | |--------+------------------------------------------------------------------------------------------------------------------------------------------------------+------------| | 398 | [[./src/randompickindex][Random Pick Index]] | Medium | | 397 | [[./src/integer_replacement][Integer Replacement]] | Medium | | 396 | [[./src/rotate_function][Rotate Function]] | Medium | | 395 | [[./src/longestsubstringwithatleastkrepeating_characters][Longest Substring with At Least K Repeating Characters]] | Medium | | 394 | [[./src/decode_string][Decode String]] | Medium | | 393 | [[./src/utf8validation][UTF-8 Validation]] | Medium | | 392 | [[./src/is_subsequence][Is Subsequence]] | Easy | | 391 | [[./src/perfect_rectangle][Perfect Rectangle]] | Hard | | 390 | [[./src/elimination_game][Elimination Game]] | Medium | | 389 | [[./src/findthedifference][Find the Difference]] | Easy | | 388 | [[./src/longestabsolutefile_path][Longest Absolute File Path]] | Medium | | 387 | [[./src/firstuniquecharacterina_string][First Unique Character in a String]] | Easy | | 386 | [[./src/lexicographical_numbers][Lexicographical Numbers]] | Medium | | 385 | [[./src/mini_parser][Mini parser]] | Medium | | 384 | [[./src/shuffleanarray][Shuffle An Array]] | Medium | | 383 | [[./src/ransom_note][Ransom Note]] | Easy | | 382 | [[./src/linkedlistrandom_note][Linked List Random Node]] | Medium | | 381 | [[./src/insertdeletegetrandomo1duplicate][Insert Delete GetRandom O(1) Duplicate]] | Hard | | 380 | [[./src/insertdeletegetrandom_o1][Insert Delete GetRandom O(1)]] | Medium | | 379 | [[./src/designphonedirectory][Design Phone Directory]] | Medium | | 378 | [[./src/kthsmallestsorted_matrix][Kth Smallest Element in a Sorted Matrix]] | Medium | | 377 | [[./src/combinationsumiv][Combination Sum IV]] | Medium | | 376 | [[./src/wiggle_sequence][Wiggle sequence]] | Medium | | 375 | [[./src/guessnumberhigherorlower_ii][Guess number higher or lower ii]] | Medium | | 374 | [[./src/guessnumberhigherorlower][Guess number higher or lower]] | Easy | | 373 | [[./src/findkpairswithsmallest_sums][Find K Pairs with Smallest Sums]] | Medium | | 372 | [[./src/super_pow][Super Pow]] | Medium | | 371 | [[./src/sumoftwo_integers][Sum of Two Integers]] | Easy | | 370 | [[./src/range_addition][Range Addition]] | Medium | | 369 | [[./src/plusonelinked_list][Plus One Linked List]] | Medium | | 368 | [[./src/largestdivisiblesubset][Largest divisible subset]] | Medium | | 367 | [[./src/validperfectsquare][Valid Perfect Square]] | Medium | | 366 | [[./src/findleavesofbinarytree][Find Leaves of Binary Tree]] | Medium | | 365 | [[./src/waterandjug_problem][Water and Jug Problem]] | Medium | | 364 | [[./src/nestedlistweightsumii][Nested List Weight Sum II]] | Medium | | 363 | [[./src/maxsumofrectanglenolargerthan_k][Max Sum of Rectangle No Larger Than K]] | Hard | | 362 | [[./src/designhitcounter][Design Hit Counter]] | Medium | | 361 | [[./src/bomb_enemy][Bomb Enemy]] | Medium | | 360 | [[./src/sorttransformedarray][Sort Transformed Array]] | Medium | | 359 | [[./src/loggerratelimiter][Logger Rate Limiter]] | Easy | | 358 | [[./src/rearrangestringkdistanceapart][Rearrage String K distance Apart]] | Hard | | 357 | [[./src/countnumberswithuniquedigits][Count Numbers with Unique Digits]] | Medium | | 356 | [[./src/line_reflection][Line Reflection]] | Medium | | 355 | [[./src/design_twitter][Design Twitter]] | Medium | | 354 | [[./src/russiandollenvelopes][Russian Doll Envelopes]] | Hard | | 353 | [[./src/designsnakegame][Design Snake Game]] | Medium | | 352 | [[./src/datastreamasdisjointintervals][Data Stream as Disjoint Intervals]] | Hard | | 351 | [[./src/androidunlockpatterns][Android unlock patterns]] | Medium | | 350 | [[./src/intersectionoftwoarraysii][Intersection of Two Arrays II]] | Easy | | 349 | [[./src/intersectionoftwo_arrays][Intersection of Two Arrays]] | Easy | | 348 | [[./src/designtictac_toe][Design tic-tac-toe]] | Medium | | 347 | [[./src/topkfrequent_elements][Top K frequent elements]] | Medium | | 346 | [[./src/movingaveragefromdatastream][Moving Average from data stream]] | Easy | | 345 | [[./src/reversevowelsofastring][Reverse Vowels of a String]] | Easy | | 344 | [[./src/reverse_string][Reverse String]] | Easy | | 343 | [[./src/integer_break][Integer Break]] | Medium | | 342 | [[./src/poweroffour][Power of Four]] | Easy | | 341 | [[./src/flattennestedlist_iterator][Flatten Nested List Iterator]] | Medium | | 340 | [[./src/longestsubstringwithatmostkdistinct_characters][Longest Substring with At Most K Distinct Characters]] | Hard | | 339 | [[./src/nestedlistweight_sum][Nested List Weight Sum]] | Easy | | 338 | [[./src/counting_bits][Counting Bits]] | Medium | | 337 | [[./src/houserobberiii][House Robber III]] | Medium | | 336 | [[./src/palindrome_pairs][Palindrome Pairs]] | Hard | | 335 | [[./src/self_crossing][Self Crossing]] | Hard | | 334 | [[./src/increasingtripletsubsequence][Increasing Triplet Subsequence]] | Medium | | 333 | [[./src/largestbstsubtree][Largest BST subtree]] | Medium | | 332 | [[./src/reconstruct_itinerary][Reconstruct Itinerary]] | Medium | | 331 | [[./src/verifypreorderserializationofabinarytree][Verify Preorder Serialization of a Binary Tree]] | Medium | | 330 | [[./src/patching_array][Patching Array]] | Medium | | 329 | [[./src/longestincreasingpathina_matrix][Longest Increasing Path in a Matrix]] | Hard | | 328 | [[./src/oddevenlinked_list][Odd Even Linked List]] | Easy | | 327 | [[./src/countofrange_sum][Count of Range Sum]] | Hard | | 326 | [[./src/powerofthree][Power of Three]] | Easy | | 325 | [[./src/maximumsizesubarraysumequals_k][Maximum Size Subarray Sum Equals k]] | Easy | | 324 | [[./src/wigglesortii][Wiggle Sort II]] | Medium | | 323 | [[./src/numberofconnected_components][Number of Connected Components]] | Medium | | 322 | [[./src/coin_change][Coin Change]] | Medium | | 321 | [[./src/createmaximumnumber][Create Maximum Number]] | Hard | | 320 | [[./src/generalized_abbreviation][Generalized Abbreviation]] | Medium | | 319 | [[./src/bulb_switcher][Bulb Switcher]] | Medium | | 318 | [[./src/maximumproductofwordlengths][Maximum Product of Word Lengths]] | Medium | | 317 | [[./src/shortestdistancefromallbuildings][Shortest Distance from All Buildings]] | Hard | | 316 | [[./src/removeduplicateletters][Remove Duplicate Letters]] | Medium | | 315 | [[./src/countofsmallernumberafter_self][Count of Smaller Numbers After Self]] | Hard | | 314 | [[./src/binarytreeverticalordertraversal][Binary Tree Vertical Order Traversal]] | Medium | | 313 | [[./src/superuglynumber][Super Ugly Number]] | Medium | | 312 | [[./src/burst_balloons][Burst Balloons]] | Medium | | 311 | [[./src/sparsematrixmultiplication][Sparse Matrix Multiplication]] | Medium | | 310 | [[./src/minimumheighttrees][Minimum Height Trees]] | Medium | | 309 | [[./src/besttimetobuyandsellstockwithcooldown][Best Time to Buy and Sell Stock with Cooldown]] | Medium | | 308 | [[./src/rangesumquery2dmutable][Range Sum Query 2D - Mutable]] | Hard | | 307 | [[./src/rangesumquery_mutable][Range Sum Query - Mutable]] | Medium | | 306 | [[./src/additive_number][Additive Number]] | Medium | | 305 | [[./src/numberofislands_ii][Number of Islands II]] | Hard | | 304 | [[./src/rangesumquery2dimmutable][Range Sum Query 2D - Immutable]] | Medium | | 303 | [[./src/rangesumquery_immutable][Range Sum Query - Immutable]] | Easy | | 302 | [[./src/smallestrectangleenclosingblackpixels][Smallest Rectangle Enclosing Black Pixels]] | Hard | | 301 | [[./src/removeinvalidparentheses][Remove Invalid Parentheses]] | Hard | | 300 | [[./src/longestincreasingsubsequence][Longest Increasing Subsequence]] | Medium | | 299 | [[./src/bullsandcows][Bulls and Cows]] | Easy | | 298 | [[./src/binarytreelongestconsecutivesequence][Binary Tree Longest Consecutive Sequence]] | Medium | | 297 | [[./src/serializeanddeserializebinarytree][Serialize and Deserialize Binary Tree]] | Medium | | 296 | [[./src/bestmeetingpoint][Best Meeting Point]] | Hard | | 295 | [[./src/findmedianfromdatastream][Find Median from Data Stream]] | Hard | | 294 | [[./src/flipgameii][Flip Game II]] | Medium | | 293 | [[./src/flip_game][Flip Game]] | Easy | | 292 | [[./src/nim_game][Nim Game]] | Easy | | 291 | [[./src/wordpatternii][Word Pattern II]] | Hard | | 290 | [[./src/word_pattern][Word Pattern]] | Easy | | 289 | [[./src/gameoflife][Game of Life]] | Medium | | 288 | [[./src/uniquewordabbreviation][Unique Word Abbreviation]] | Easy | | 287 | [[./src/findtheduplicate_number][Find the Duplicate Number]] | Hard | | 286 | [[./src/wallsandgates][Walls and Gates]] | Medium | | 285 | [[./src/inordersuccessorin_bst][Inorder Successor in BST]] | Medium | | 284 | [[./src/peeking_iterator][Peeking Iterator]] | Medium | | 283 | [[./src/moving_zeroes][Moving Zeroes]] | Easy | | 282 | [[./src/expressionaddoperators][Expression Add Operators]] | Hard | | 281 | [[./src/zigzag_iterator][Zigzag Iterator]] | Medium | | 280 | [[./src/wiggle_sort][Wiggle Sort]] | Medium | | 279 | [[./src/perfect_squares][Perfect Squares]] | Medium | | 278 | [[./src/firstbadversion][First Bad Version]] | Easy | | 277 | [[./src/findthecelebrity][Find the Celebrity]] | Medium | | 276 | [[./src/paint_fence][Paint Fence]] | Easy | | 275 | [[./src/hindexii][H Index II]] | Medium | | 274 | [[./src/h_index][H Index]] | Medium | | 273 | [[./src/integertoenglish_words][Integer to English Words]] | Medium | | 272 | [[./src/closestbinarysearchtreevalue_ii][Closest Binary Search Tree Value II]] | Hard | | 271 | [[./src/encodeanddecode_strings][Encode and Decode Strings]] | Medium | | 270 | [[./src/closestbinarysearchtreevalue][Closest Binary Search Tree Value]] | Easy | | 269 | [[./src/alien_dictionary][Alien Dictionary]] | Hard | | 268 | [[./src/missing_number][Missing Number]] | Medium | | 267 | [[./src/palindromepermutationii][Palindrome Permutation II]] | Medium | | 266 | [[./src/palindrome_permutation][Palindrome Permutation]] | Easy | | 265 | [[./src/painthouseii][Paint House II]] | Hard | | 264 | [[./src/uglynumberii][Ugly Number II]] | Medium | | 263 | [[./src/ugly_number][Ugly Number]] | Easy | | 261 | [[./src/graphvalidtree][Graph Valid Tree]] | Medium | | 260 | [[./src/singlenumberiii][Single Number III]] | Medium | | 259 | [[./src/3sum_smaller][3Sum Smaller]] | Medium | | 258 | [[./src/add_digits][Add Digits]] | Easy | | 257 | [[./src/binarytreepaths][Binary Tree Paths]] | Easy | | 256 | [[./src/paint_house][Paint House]] | Medium | | 255 | [[./src/verifypreordersequenceinbinarysearchtree][Verify Preorder Sequence in Binary Search Tree]] | Medium | | 254 | [[./src/factor_combinations][Factor Combinations]] | Medium | | 253 | [[./src/meetingroomsii][Meeting Rooms II]] | Medium | | 252 | [[./src/meeting_rooms][Meeting Rooms]] | Easy | | 251 | [[./src/flatten2dvector][Flatten 2D Vector]] | Medium | | 250 | [[./src/countunivaluesubtrees][Count Univalue Subtrees]] | Medium | | 249 | [[./src/groupshiftedstrings][Group Shifted Strings]] | Easy | | 248 | [[./src/strobogrammaticnumberiii][Strobogrammatic Number III]] | Hard | | 247 | [[./src/strobogrammaticnumberii][Strobogrammatic Number II]] | Medium | | 246 | [[./src/strobogrammatic_number][Strobogrammatic Number]] | Easy | | 245 | [[./src/shortestworddistance_iii][Shortest Word Distance III]] | Medium | | 244 | [[./src/shortestworddistance_ii][Shortest Word Distance II]] | Medium | | 243 | [[./src/shortestworddistance][Shortest Word Distance]] | Easy | | 242 | [[https://leetcode.com/problems/valid-anagram/][Valid Anagram]] | Easy | | 241 | [[https://leetcode.com/problems/different-ways-to-add-parentheses/][Different Ways to Add Parentheses]] | Medium | | 240 | [[https://leetcode.com/problems/search-a-2d-matrix-ii/][Search a 2D Matrix II]] | Medium | | 239 | [[https://leetcode.com/problems/sliding-window-maximum/][Sliding Window Maximum]] | Hard | | 238 | [[https://leetcode.com/problems/product-of-array-except-self/][Product of Array Except Self]] | Medium | | 237 | [[https://leetcode.com/problems/delete-node-in-a-linked-list/][Delete Node in a Linked List]] | Easy | | 236 | [[https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-tree/][Lowest Common Ancestor of a Binary Tree]] | Medium | | 235 | [[https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/][Lowest Common Ancestor of a Binary Search Tree]] | Easy | | 234 | [[https://leetcode.com/problems/palindrome-linked-list/][Palindrome Linked List]] | Easy | | 233 | [[https://leetcode.com/problems/number-of-digit-one/][Number of Digit One]] | Medium | | 232 | [[https://leetcode.com/problems/implement-queue-using-stacks/][Implement Queue using Stacks]] | Easy | | 231 | [[https://leetcode.com/problems/power-of-two/][Power of Two]] | Easy | | 230 | [[https://leetcode.com/problems/kth-smallest-element-in-a-bst/][Kth Smallest Element in a BST]] | Medium | | 229 | [[https://leetcode.com/problems/majority-element-ii/][Majority Element II]] | Medium | | 228 | [[https://leetcode.com/problems/summary-ranges/][Summary Ranges]] | Easy | | 227 | [[https://leetcode.com/problems/basic-calculator-ii/][Basic Calculator II]] | Medium | | 226 | [[https://leetcode.com/problems/invert-binary-tree/][Invert Binary Tree]] | Easy | | 225 | [[https://leetcode.com/problems/implement-stack-using-queues/][Implement Stack using Queues]] | Medium | | 224 | [[https://leetcode.com/problems/basic-calculator/][Basic Calculator]] | Medium | | 223 | [[https://leetcode.com/problems/rectangle-area/][Rectangle Area]] | Easy | | 222 | [[https://leetcode.com/problems/count-complete-tree-nodes/][Count Complete Tree Nodes]] | Medium | | 221 | [[https://leetcode.com/problems/maximal-square/][Maximal Square]] | Medium | | 220 | [[https://leetcode.com/problems/contains-duplicate-iii/][Contains duplicate iii]] | Medium | | 219 | [[https://leetcode.com/problems/contains-duplicate-ii/][Contains duplicate ii]] | Easy | | 218 | [[https://leetcode.com/problems/the-skyline-problem/][The Skyline Problem]] | Hard | | 217 | [[https://leetcode.com/problems/contains-duplicate/][Contains duplicate]] | Easy | | 216 | [[https://leetcode.com/problems/combination-sum-iii/][Combination Sum III]] | Medium | | 215 | [[https://leetcode.com/problems/kth-largest-element-in-an-array/][Kth Largest Element in an Array]] | Medium | | 214 | [[https://leetcode.com/problems/shortest-palindrome/][Shortest Palindrome]] | Hard | | 213 | [[https://leetcode.com/problems/house-robber-ii/][House robber II]] | Medium | | 212 | [[https://leetcode.com/problems/word-search-ii/][Word search II]] | Hard | | 211 | [[https://leetcode.com/problems/add-and-search-word-data-structure-design/][Add and Search Word]] | Medium | | 210 | [[https://leetcode.com/problems/course-schedule-ii/][Course schedule II]] | Medium | | 209 | [[https://leetcode.com/problems/minimum-size-subarray-sum/][Minimum Size Subarray Sum]] | Medium | | 208 | [[https://leetcode.com/problems/implement-trie-prefix-tree/][Implement Trie]] | Medium | | 207 | [[https://leetcode.com/problems/course-schedule/][Course schedule]] | Medium | | 205 | [[https://leetcode.com/problems/reverse-linked-list/][Revese linkedlist]] | Easy | | 205 | [[https://leetcode.com/problems/isomorphic-strings/][Isomorphic Strings]] | Easy | | 204 | [[https://leetcode.com/problems/count-primes/][Count primes]] | Medium | | 203 | [[https://leetcode.com/problems/remove-linked-list-elements/][Remove Linked List Elements]] | Easy | | 202 | [[https://leetcode.com/problems/happy-number/][Happy Number]] | Easy | | 201 | [[https://leetcode.com/problems/bitwise-and-of-numbers-range/][Bitwise AND of Numbers Range]] | Medium | | 200 | [[https://leetcode.com/problems/number-of-islands/][Number of islands]] | Medium | | 199 | [[https://leetcode.com/problems/binary-tree-right-side-view/][Binary tree right side view]] | Medium | | 198 | [[https://leetcode.com/problems/house-robber/][House robber]] | Easy | | 191 | [[https://leetcode.com/problems/number-of-1-bits/][Number of 1 bits]] | Easy | | 190 | [[https://oj.leetcode.com/problems/reverse-bits/][Reverse bits]] | Easy | | 189 | [[https://oj.leetcode.com/problems/rotate-array/][Rotate array]] | Easy | | 188 | [[https://oj.leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/][Best Time to Buy and Sell Stock IV]] | Hard | | 187 | [[https://oj.leetcode.com/problems/repeated-dna-sequences/][Repeated DNA Sequences]] | Medium | | 176 | [[https://oj.leetcode.com/problems/reverse-words-in-a-string-ii/][Reverse Words in a String II]] | Medium | | 179 | [[https://oj.leetcode.com/problems/largest-number/][Largest Number]] | Medium | | 174 | [[https://oj.leetcode.com/problems/dungeon-game/][Dungeon Game]] | Hard | | 173 | [[https://oj.leetcode.com/problems/binary-search-tree-iterator/][Binary Search Tree Iterator]] | Medium | | 172 | [[https://oj.leetcode.com/problems/factorial-trailing-zeroes/][Factorial Trailing Zeroes]] | Easy | | 171 | [[https://oj.leetcode.com/problems/excel-sheet-column-number/][Excel Sheet Column Number]] | Easy | | 169 | [[https://oj.leetcode.com/problems/majority-element/][Majority Element]] | Easy | | 168 | [[https://oj.leetcode.com/problems/excel-sheet-column-title/][Excel Sheet Column Title]] | Easy | | 166 | [[https://oj.leetcode.com/problems/fraction-to-recurring-decimal/][Fraction to Recurring Decimal]] | Medium | | 165 | [[https://oj.leetcode.com/problems/compare-version-numbers/][Compare Version Numbers]] | Easy | | 164 | [[https://oj.leetcode.com/problems/maximum-gap/][Maximum Gap]] | Hard | | 163 | [[https://oj.leetcode.com/problems/missing-ranges/][Missing Ranges]] | Medium | | 162 | [[https://oj.leetcode.com/problems/find-peak-element/][Find Peak Element]] | Medium | | 161 | [[https://oj.leetcode.com/problems/one-edit-distance/][One Edit Distance]] | Medium | | 160 | [[https://oj.leetcode.com/problems/intersection-of-two-linked-lists/][Intersection of Two Linked Lists]] | Easy | | 159 | [[https://oj.leetcode.com/problems/longest-substring-with-at-most-two-distinct-characters/][Longest Substring with At Most Two Distinct Characters]] | Hard | | 158 | [[https://oj.leetcode.com/problems/read-n-characters-given-read4-ii-call-multiple-times/][Read N Characters Given Read4 II - Call multiple times]] | Hard | | 157 | [[https://oj.leetcode.com/problems/read-n-characters-given-read4/][Read N Characters Given Read4]] | Easy | | 156 | [[https://oj.leetcode.com/problems/binary-tree-upside-down/][Binary Tree Upside Down]] | Medium | | 155 | [[https://oj.leetcode.com/problems/min-stack/][Min Stack]] | Easy | | 154 | [[https://oj.leetcode.com/problems/find-minimum-in-rotated-sorted-array-ii/][Find Minimum in Rotated Sorted Array II]] | Hard | | 153 | [[https://oj.leetcode.com/problems/find-minimum-in-rotated-sorted-array/][Find Minimum in Rotated Sorted Array]] | Medium | | 152 | [[https://oj.leetcode.com/problems/maximum-product-subarray/][Maximum Product Subarray]] | Medium | | 151 | [[https://oj.leetcode.com/problems/reverse-words-in-a-string/][Reverse Words in a String]] | Medium | | 150 | [[https://oj.leetcode.com/problems/evaluate-reverse-polish-notation/][Evaluate Reverse Polish Notation]] | Medium | | 149 | [[https://oj.leetcode.com/problems/max-points-on-a-line/][Max Points on a Line]] | Hard | | 148 | [[https://oj.leetcode.com/problems/sort-list/][Sort List]] | Medium | | 147 | [[https://oj.leetcode.com/problems/insertion-sort-list/][Insertion Sort List]] | Medium | | 146 | [[https://oj.leetcode.com/problems/lru-cache/][LRU Cache]] | Hard | | 145 | [[https://oj.leetcode.com/problems/binary-tree-postorder-traversal/][Binary Tree Postorder Traversal]] | Hard | | 144 | [[https://oj.leetcode.com/problems/binary-tree-preorder-traversal/][Binary Tree Preorder Traversal]] | Medium | | 143 | [[https://oj.leetcode.com/problems/reorder-list/][Reorder List]] | Medium | | 142 | [[https://oj.leetcode.com/problems/linked-list-cycle-ii/][Linked List Cycle II]] | Medium | | 141 | [[https://oj.leetcode.com/problems/linked-list-cycle/][Linked List Cycle]] | Medium | | 140 | [[https://oj.leetcode.com/problems/word-break-ii/][Word Break II]] | Hard | | 139 | [[https://oj.leetcode.com/problems/word-break/][Word Break]] | Medium | | 138 | [[https://oj.leetcode.com/problems/copy-list-with-random-pointer/][Copy List with Random Pointer]] | Hard | | 137 | [[https://oj.leetcode.com/problems/single-number-ii/][Single Number II]] | Medium | | 136 | [[https://oj.leetcode.com/problems/single-number/][Single Number]] | Medium | | 135 | [[https://oj.leetcode.com/problems/candy/][Candy]] | Hard | | 134 | [[https://oj.leetcode.com/problems/gas-station/][Gas Station]] | Medium | | 133 | [[https://oj.leetcode.com/problems/clone-graph/][Clone Graph]] | Medium | | 132 | [[https://oj.leetcode.com/problems/palindrome-partitioning-ii/][Palindrome Partitioning II]] | Hard | | 131 | [[https://oj.leetcode.com/problems/palindrome-partitioning/][Palindrome Partitioning]] | Medium | | 130 | [[https://oj.leetcode.com/problems/surrounded-regions/][Surrounded Regions]] | Medium | | 129 | [[https://oj.leetcode.com/problems/sum-root-to-leaf-numbers/][Sum Root to Leaf Numbers]] | Medium | | 128 | [[https://oj.leetcode.com/problems/longest-consecutive-sequence/][Longest Consecutive Sequence]] | Hard | | 127 | [[https://oj.leetcode.com/problems/word-ladder-ii/][Word Ladder II]] | Hard | | 126 | [[https://oj.leetcode.com/problems/word-ladder/][Word Ladder]] | Medium | | 125 | [[https://oj.leetcode.com/problems/valid-palindrome/][Valid Palindrome]] | Easy | | 124 | [[https://oj.leetcode.com/problems/binary-tree-maximum-path-sum/][Binary Tree Maximum Path Sum]] | Hard | | 123 | [[https://oj.leetcode.com/problems/best-time-to-buy-and-sell-stock-iii/][Best Time to Buy and Sell Stock III]] | Hard | | 122 | [[https://oj.leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/][Best Time to Buy and Sell Stock II]] | Medium | | 121 | [[https://oj.leetcode.com/problems/best-time-to-buy-and-sell-stock/][Best Time to Buy and Sell Stock]] | Medium | | 120 | [[https://oj.leetcode.com/problems/triangle/][Triangle]] | Medium | | 119 | [[https://oj.leetcode.com/problems/pascals-triangle-ii/][Pascal's Triangle II]] | Easy | | 118 | [[https://oj.leetcode.com/problems/pascals-triangle/][Pascal's Triangle]] | Easy | | 117 | [[https://oj.leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/][Populating Next Right Pointers in Each Node II]] | Hard | | 116 | [[https://oj.leetcode.com/problems/populating-next-right-pointers-in-each-node/][Populating Next Right Pointers in Each Node]] | Medium | | 115 | [[https://oj.leetcode.com/problems/distinct-subsequences/][Distinct Subsequences]] | Hard | | 114 | [[https://oj.leetcode.com/problems/flatten-binary-tree-to-ed-list/][Flatten Binary Tree to Linked List]] | Medium | | 113 | [[https://oj.leetcode.com/problems/path-sum-ii/][Path Sum II]] | Medium | | 112 | [[https://oj.leetcode.com/problems/path-sum/][Path Sum]] | Easy | | 111 | [[https://oj.leetcode.com/problems/minimum-depth-of-binary-tree/][Minimum Depth of Binary Tree]] | Easy | | 110 | [[https://oj.leetcode.com/problems/balanced-binary-tree/][Balanced Binary Tree]] | Easy | | 109 | [[https://oj.leetcode.com/problems/convert-sorted-list-to-binary-search-tree/][Convert Sorted List to Binary Search Tree]] | Medium | | 108 | [[https://oj.leetcode.com/problems/convert-sorted-array-to-binary-search-tree/][Convert Sorted Array to Binary Search Tree]] | Medium | | 107 | [[https://oj.leetcode.com/problems/binary-tree-level-order-traversal-ii/][Binary Tree Level Order Traversal II]] | Easy | | 106 | [[https://oj.leetcode.com/problems/construct-binary-tree-from-inorder-and-postorder-traversal/][Construct Binary Tree from Inorder and Postorder]] | Medium | | 105 | [[https://oj.leetcode.com/problems/construct-binary-tree-from-preorder-and-inorder-traversal/][Construct Binary Tree from Preorder and Inorder]] | Medium | | 104 | [[https://oj.leetcode.com/problems/maximum-depth-of-binary-tree/][Maximum Depth of Binary Tree]] | Easy | | 103 | [[https://oj.leetcode.com/problems/binary-tree-zigzag-level-order-traversal/][Binary Tree Zigzag Level Order Traversal]] | Medium | | 102 | [[https://oj.leetcode.com/problems/binary-tree-level-order-traversal/][Binary Tree Level Order Traversal]] | Easy | | 101 | [[https://oj.leetcode.com/problems/symmetric-tree/][Symmetric Tree]] | Easy | | 100 | [[https://oj.leetcode.com/problems/same-tree/][Same Tree]] | Easy | | 99 | [[https://oj.leetcode.com/problems/recover-binary-search-tree/][Recover Binary Search Tree]] | Hard | | 98 | [[https://oj.leetcode.com/problems/validate-binary-search-tree/][Validate Binary Search Tree]] | Medium | | 97 | [[https://oj.leetcode.com/problems/interleaving-string/][Interleaving String]] | Hard | | 96 | [[https://oj.leetcode.com/problems/unique-binary-search-trees-ii/][Unique Binary Search Trees II]] | Medium | | 95 | [[https://oj.leetcode.com/problems/unique-binary-search-trees/][Unique Binary Search Trees]] | Medium | | 94 | [[https://oj.leetcode.com/problems/binary-tree-inorder-traversal/][Binary Tree Inorder Traversal]] | Medium | | 93 | [[https://oj.leetcode.com/problems/restore-ip-addresses/][Restore IP Addresses]] | Medium | | 92 | [[https://oj.leetcode.com/problems/reverse-ed-list-ii/][Reverse linked List II]] | Medium | | 91 | [[https://oj.leetcode.com/problems/subsets-ii/][Subsets II]] | Medium | | 90 | [[https://oj.leetcode.com/problems/decode-ways/][Decode Ways]] | Medium | | 89 | [[https://oj.leetcode.com/problems/gray-code/][Gray Code]] | Medium | | 88 | [[https://oj.leetcode.com/problems/merge-sorted-array/][Merge Sorted Array]] | Easy | | 87 | [[https://oj.leetcode.com/problems/scramble-string/][Scramble String]] | Hard | | 86 | [[https://oj.leetcode.com/problems/partition-list/][Partition List]] | Medium | | 85 | [[https://oj.leetcode.com/problems/maximal-rectangle/][Maximal Rectangle]] | Hard | | 84 | [[https://oj.leetcode.com/problems/largest-rectangle-in-histogram/][Largest Rectangle in Histogram]] | Hard | | 83 | [[https://oj.leetcode.com/problems/remove-duplicates-from-sorted-list-ii/][Remove Duplicates from Sorted List II]] | Medium | | 82 | [[https://oj.leetcode.com/problems/remove-duplicates-from-sorted-list/][Remove Duplicates from Sorted List]] | Easy | | 81 | [[https://oj.leetcode.com/problems/search-in-rotated-sorted-array-ii/][Search in Rotated Sorted Array II]] | Medium | | 80 | [[https://oj.leetcode.com/problems/remove-duplicates-from-sorted-array-ii/][Remove Duplicates from Sorted Array II]] | Medium | | 79 | [[https://oj.leetcode.com/problems/word-search/][Word Search]] | Medium | | 78 | [[https://oj.leetcode.com/problems/subsets/][Subsets]] | Medium | | 77 | [[https://oj.leetcode.com/problems/combinations/][Combinations]] | Medium | | 76 | [[https://oj.leetcode.com/problems/minimum-window-substring/][Minimum Window Substring]] | Hard | | 75 | [[https://oj.leetcode.com/problems/sort-colors/][Sort Colors]] | Medium | | 74 | [[https://oj.leetcode.com/problems/search-a-2d-matrix/][Search a 2D Matrix]] | Medium | | 73 | [[https://oj.leetcode.com/problems/set-matrix-zeroes/][Set Matrix Zeroes]] | Medium | | 72 | [[https://oj.leetcode.com/problems/edit-distance/][Edit Distance]] | Hard | | 71 | [[https://oj.leetcode.com/problems/simplify-path/][Simplify Path]] | Medium | | 70 | [[https://oj.leetcode.com/problems/climbing-stairs/][Climbing Stairs]] | Easy | | 69 | [[https://oj.leetcode.com/problems/sqrtx/][Sqrt(x)]] | Medium | | 68 | [[https://oj.leetcode.com/problems/text-justification/][Text Justification]] | Hard | | 67 | [[https://oj.leetcode.com/problems/plus-one/][Plus One]] | Easy | | 66 | [[https://oj.leetcode.com/problems/valid-number/][Valid Number]] | Easy | | 65 | [[https://oj.leetcode.com/problems/add-binary/][Add Binary]] | Easy | | 64 | [[https://oj.leetcode.com/problems/merge-two-sorted-lists/][Merge Two Sorted Lists]] | Easy | | 63 | [[https://oj.leetcode.com/problems/minimum-path-sum/][Minimum Path Sum]] | Medium | | 62 | [[https://oj.leetcode.com/problems/unique-paths-ii/][Unique Paths II]] | Medium | | 61 | [[https://oj.leetcode.com/problems/unique-paths/][Unique Paths]] | Medium | | 60 | [[https://oj.leetcode.com/problems/rotate-list/][Rotate List]] | Medium | | 59 | [[https://oj.leetcode.com/problems/permutation-sequence/][Permutation Sequence]] | Medium | | 58 | [[https://oj.leetcode.com/problems/spiral-matrix-ii/][Spiral Matrix II]] | Medium | | 57 | [[https://oj.leetcode.com/problems/length-of-last-word/][Length of Last Word]] | Easy | | 56 | [[https://oj.leetcode.com/problems/insert-interval/][Insert Interval]] | Hard | | 55 | [[https://oj.leetcode.com/problems/merge-intervals/][Merge Intervals]] | Hard | | 54 | [[https://oj.leetcode.com/problems/jump-game/][Jump Game]] | Medium | | 53 | [[https://oj.leetcode.com/problems/spiral-matrix/][Spiral Matrix]] | Medium | | 52 | [[https://oj.leetcode.com/problems/maximum-subarray/][Maximum Subarray]] | Medium | | 51 | [[https://oj.leetcode.com/problems/n-queens-ii/][N-Queens II]] | Hard | | 50 | [[https://oj.leetcode.com/problems/n-queens/][N-Queens]] | Hard | | 49 | [[https://oj.leetcode.com/problems/powx-n/]["Pow(x, n)"]] | Medium | | 48 | [[https://oj.leetcode.com/problems/anagrams/][Anagrams]] | Medium | | 47 | [[https://oj.leetcode.com/problems/rotate-image/][Rotate Image]] | Medium | | 46 | [[https://oj.leetcode.com/problems/permutations-ii/][Permutations II]] | Hard | | 45 | [[https://oj.leetcode.com/problems/permutations/][Permutations]] | Medium | | 44 | [[https://oj.leetcode.com/problems/jump-game-ii/][Jump Game II]] | Hard | | 43 | [[https://oj.leetcode.com/problems/wildcard-matching/][Wildcard Matching]] | Hard | | 41 | [[https://oj.leetcode.com/problems/trapping-rain-water/][Trapping Rain Water]] | Hard | | 40 | [[https://oj.leetcode.com/problems/first-missing-positive/][First Missing Positive]] | Hard | | 39 | [[https://oj.leetcode.com/problems/combination-sum-ii/][Combination Sum II]] | Medium | | 38 | [[https://oj.leetcode.com/problems/combination-sum/][Combination Sum]] | Medium | | 37 | [[https://oj.leetcode.com/problems/count-and-say/][Count and Say]] | Easy | | 36 | [[https://oj.leetcode.com/problems/sudoku-solver/][Sudoku Solver]] | Hard | | 35 | [[https://oj.leetcode.com/problems/valid-sudoku/][Valid Sudoku]] | Easy | | 34 | [[https://oj.leetcode.com/problems/search-insert-position/][Search Insert Position]] | Medium | | 33 | [[https://oj.leetcode.com/problems/search-for-a-range/][Search for a Range]] | Medium | | 31 | [[https://oj.leetcode.com/problems/longest-valid-parentheses/][Longest Valid Parentheses]] | Hard | | 32 | [[https://oj.leetcode.com/problems/search-in-rotated-sorted-array/][Search in Rotated Sorted Array]] | Hard | | 30 | [[https://oj.leetcode.com/problems/next-permutation/][Next Permutation]] | Medium | | 29 | [[https://oj.leetcode.com/problems/substring-with-concatenation-of-all-words/][Substring with Concatenation of All Words]] | Hard | | 28 | [[https://oj.leetcode.com/problems/divide-two-integers/][Divide Two Integers]] | Medium | | 27 | [[https://oj.leetcode.com/problems/implement-strstr/][Implement strStr()]] | Easy | | 26 | [[https://oj.leetcode.com/problems/remove-element/][Remove Element]] | Easy | | 25 | [[https://oj.leetcode.com/problems/remove-duplicates-from-sorted-array/][Remove Duplicates from Sorted Array]] | Easy | | 24 | [[https://oj.leetcode.com/problems/reverse-nodes-in-k-group/][Reverse Nodes in k-Group]] | Hard | | 23 | [[https://oj.leetcode.com/problems/swap-nodes-in-pairs/][Swap Nodes in Pairs]] | Medium | | 22 | [[https://oj.leetcode.com/problems/merge-k-sorted-lists/][Merge k Sorted Lists]] | Hard | | 21 | [[https://oj.leetcode.com/problems/generate-parentheses/][Generate Parentheses]] | Medium | | 20 | [[https://oj.leetcode.com/problems/valid-parentheses/][Valid Parentheses]] | Easy | | 19 | [[https://oj.leetcode.com/problems/remove-nth-node-from-end-of-list/][Remove Nth Node From End of List]] | Easy | | 18 | [[https://oj.leetcode.com/problems/letter-combinations-of-a-phone-number/][Letter Combinations of a Phone Number]] | Medium | | 17 | [[https://oj.leetcode.com/problems/4sum/][4Sum]] | Medium | | 16 | [[https://oj.leetcode.com/problems/3sum-closest/][3Sum Closest]] | Medium | | 15 | [[https://oj.leetcode.com/problems/3sum/][3Sum]] | Medium | | 14 | [[https://oj.leetcode.com/problems/longest-common-prefix/][Longest Common Prefix]] | Easy | | 13 | [[https://oj.leetcode.com/problems/roman-to-integer/][Roman to Integer]] | Easy | | 12 | [[https://oj.leetcode.com/problems/integer-to-roman/][Integer to Roman]] | Medium | | 11 | [[https://oj.leetcode.com/problems/container-with-most-water/][Container With Most Water]] | Medium | | 10 | [[https://oj.leetcode.com/problems/regular-expression-matching/][Regular Expression Matching]] | Hard | | 9 | [[https://oj.leetcode.com/problems/palindrome-number/][Palindrome Number]] | Easy | | 8 | [[https://oj.leetcode.com/problems/string-to-integer-atoi/][String to Integer (atoi)]] | Easy | | 7 | [[https://oj.leetcode.com/problems/reverse-integer/][Reverse Integer]] | Easy | | 6 | [[https://oj.leetcode.com/problems/zigzag-conversion/][ZigZag Conversion]] | Easy | | 5 | [[https://oj.leetcode.com/problems/longest-palindromic-substring/][Longest Palindromic Substring]] | Medium | | 4 | [[https://oj.leetcode.com/problems/median-of-two-sorted-arrays/][Median of Two Sorted Arrays]] | Hard | | 3 | [[https://oj.leetcode.com/problems/longest-substring-without-repeating-characters/][Longest Substring Without Repeating Characters]] | Medium | | 2 | [[https://oj.leetcode.com/problems/add-two-numbers/][Add Two Numbers]] | Medium | | 1 | [[https://oj.leetcode.com/problems/two-sum/][Two Sum]] | Medium |