1 two-sum javascript 📝 Easy 2 add-two-numbers javascript 📝 Medium 3 longest-substring-without-repeating-characters javascript 📝 Medium 4 median-of-two-sorted-arrays javascript Hard 5 longest-palindromic-substring javascript 📝 Medium 6 zigzag-conversion javascript Easy 7 reverse-integer javascript Easy 8 string-to-integer-atoi Easy 9 palindrome-number javascript Easy 10 regular-expression-matching Hard 11 container-with-most-water 📝 Medium 12 integer-to-roman javascript Medium 13 roman-to-integer javascript Easy 14 longest-common-prefix javascript 📝 Easy 15 3sum javascript Medium 16 3sum-closest Medium 17 letter-combinations-of-a-phone-number Medium 18 4sum Medium 19 remove-nth-node-from-end-of-list javascript 📝 Easy 20 valid-parentheses javascript Easy 21 merge-two-sorted-lists javascript Easy 22 generate-parentheses Medium 23 merge-k-sorted-lists javascript Hard 24 swap-nodes-in-pairs javascript Easy 25 reverse-nodes-in-k-group javascript Hard 26 remove-duplicates-from-sorted-array javascript 📝 Easy 27 remove-element javascript 📝 Easy 28 implement-strstr javascript Easy 29 divide-two-integers Medium 30 substring-with-concatenation-of-all-words Hard 31 next-permutation 📝 Medium 32 longest-valid-parentheses Hard 33 search-in-rotated-sorted-array javascript Hard 34 search-for-a-range javascript Medium 35 search-insert-position javascript Medium 36 valid-sudoku javascript Easy 37 sudoku-solver Hard 38 count-and-say Easy 39 combination-sum Medium 40 combination-sum-ii Medium 41 first-missing-positive javascript Hard 42 trapping-rain-water Hard 43 multiply-strings Medium 44 wildcard-matching Hard 45 jump-game-ii Hard 46 permutations Medium 47 permutations-ii Medium 48 rotate-image Medium 49 anagrams javascript Medium 50 powx-n javascript Medium 51 n-queens Hard 52 n-queens-ii Hard 53 maximum-subarray Medium 54 spiral-matrix Medium 55 jump-game javascript 📝 Medium 56 merge-intervals Hard 57 insert-interval Hard 58 length-of-last-word javascript Easy 59 spiral-matrix-ii Medium 60 permutation-sequence Medium 61 rotate-list javascript Medium 62 unique-paths Medium 63 unique-paths-ii Medium 64 minimum-path-sum Medium 65 valid-number Hard 66 plus-one javascript Easy 67 add-binary javascript Easy 68 text-justification Hard 69 sqrtx javascript Medium 70 climbing-stairs javascript Easy 71 simplify-path Medium 72 edit-distance Hard 73 set-matrix-zeroes javascript Medium 74 search-a-2d-matrix Medium 75 sort-colors javascript Medium 76 minimum-window-substring Hard 77 combinations Medium 78 subsets javascript Medium 79 word-search Medium 80 remove-duplicates-from-sorted-array-ii javascript Medium 81 search-in-rotated-sorted-array-ii javascript Medium 82 remove-duplicates-from-sorted-list-ii javascript Medium 83 remove-duplicates-from-sorted-list javascript 📝 Easy 84 largest-rectangle-in-histogram Hard 85 maximal-rectangle Hard 86 partition-list javascript Medium 87 scramble-string Hard 88 merge-sorted-array javascript Easy 89 gray-code Medium 90 subsets-ii javascript Medium 91 decode-ways Medium 92 reverse-linked-list-ii javascript Medium 93 restore-ip-addresses Medium 94 binary-tree-inorder-traversal javascript Medium 95 unique-binary-search-trees-ii Medium 96 unique-binary-search-trees Medium 97 interleaving-string Hard 98 validate-binary-search-tree Medium 99 recover-binary-search-tree Hard 100 same-tree javascript Easy 101 symmetric-tree javascript 📝 Easy 102 binary-tree-level-order-traversal Easy 103 binary-tree-zigzag-level-order-traversal Medium 104 maximum-depth-of-binary-tree javascript Easy 105 construct-binary-tree-from-preorder-and-inorder-traversal Medium 106 construct-binary-tree-from-inorder-and-postorder-traversal Medium 107 binary-tree-level-order-traversal-ii Easy 108 convert-sorted-array-to-binary-search-tree Medium 109 convert-sorted-list-to-binary-search-tree Medium 110 balanced-binary-tree Easy 111 minimum-depth-of-binary-tree javascript Easy 112 path-sum Easy 113 path-sum-ii Medium 114 flatten-binary-tree-to-linked-list Medium 115 distinct-subsequences Hard 116 populating-next-right-pointers-in-each-node Medium 117 populating-next-right-pointers-in-each-node-ii Hard 118 pascals-triangle javascript Easy 119 pascals-triangle-ii javascript Easy 120 triangle javascript Medium 121 best-time-to-buy-and-sell-stock javascript 📝 Easy 122 best-time-to-buy-and-sell-stock-ii javascript 📝 Medium 123 best-time-to-buy-and-sell-stock-iii Hard 124 binary-tree-maximum-path-sum Hard 125 valid-palindrome javascript Easy 126 word-ladder-ii Hard 127 word-ladder Medium 128 longest-consecutive-sequence javascript Hard 129 sum-root-to-leaf-numbers Medium 130 surrounded-regions Medium 131 palindrome-partitioning Medium 132 palindrome-partitioning-ii Hard 133 clone-graph Medium 134 gas-station Medium 135 candy Hard 136 single-number javascript Easy 137 single-number-ii javascript Medium 138 copy-list-with-random-pointer Hard 139 word-break Medium 140 word-break-ii Hard 141 linked-list-cycle javascript 📝 Easy 142 linked-list-cycle-ii javascript Medium 143 reorder-list javascript Medium 144 binary-tree-preorder-traversal javascript Medium 145 binary-tree-postorder-traversal javascript Hard 146 lru-cache Hard 147 insertion-sort-list javascript Medium 148 sort-list Medium 149 max-points-on-a-line Hard 150 evaluate-reverse-polish-notation javascript Medium 151 reverse-words-in-a-string javascript Medium 152 maximum-product-subarray javascript Medium 153 find-minimum-in-rotated-sorted-array javascript Medium 154 find-minimum-in-rotated-sorted-array-ii javascript Hard 155 min-stack javascript Easy 156 binary-tree-upside-down 🔒 Medium 157 read-n-characters-given-read4 🔒 Easy 158 read-n-characters-given-read4-ii-call-multiple-times 🔒 Hard 159 longest-substring-with-at-most-two-distinct-characters 🔒 Hard 160 intersection-of-two-linked-lists javascript 📝 Easy 161 one-edit-distance 🔒 Medium 162 find-peak-element javascript Medium 163 missing-ranges 🔒 Medium 164 maximum-gap Hard 165 compare-version-numbers javascript Easy 166 fraction-to-recurring-decimal 📝 Medium 167 two-sum-ii-input-array-is-sorted javascript 📝 Medium 168 excel-sheet-column-title javascript Easy 169 majority-element javascript Easy 170 two-sum-iii-data-structure-design 🔒 Easy 171 excel-sheet-column-number javascript Easy 172 factorial-trailing-zeroes javascript Easy 173 binary-search-tree-iterator Medium 174 dungeon-game Hard 179 largest-number Medium 186 reverse-words-in-a-string-ii 🔒 Medium 187 repeated-dna-sequences Medium 188 best-time-to-buy-and-sell-stock-iv Hard 189 rotate-array javascript 📝 Easy 190 reverse-bits javascript Easy 191 number-of-1-bits javascript 📝 Easy 198 house-robber javascript 📝 Easy 199 binary-tree-right-side-view Medium 200 number-of-islands Medium 201 bitwise-and-of-numbers-range Medium 202 happy-number javascript Easy 203 remove-linked-list-elements javascript Easy 204 count-primes javascript Easy 205 isomorphic-strings javascript Easy 206 reverse-linked-list javascript 📝 Easy 207 course-schedule Medium 208 implement-trie-prefix-tree 📝 Medium 209 minimum-size-subarray-sum Medium 210 course-schedule-ii Medium 211 add-and-search-word-data-structure-design Medium 212 word-search-ii Hard 213 house-robber-ii Medium 214 shortest-palindrome Hard 215 kth-largest-element-in-an-array Medium 216 combination-sum-iii Medium 217 contains-duplicate javascript 📝 Easy 218 the-skyline-problem Hard 219 contains-duplicate-ii javascript 📝 Easy 220 contains-duplicate-iii 📝 Medium 221 maximal-square 📝 Medium 222 count-complete-tree-nodes Medium 223 rectangle-area javascript Easy 224 basic-calculator Hard 225 implement-stack-using-queues javascript 📝 Easy 226 invert-binary-tree javascript 📝 Easy 227 basic-calculator-ii Medium 228 summary-ranges javascript 📝 Medium 229 majority-element-ii javascript Medium 230 kth-smallest-element-in-a-bst Medium 231 power-of-two javascript Easy 232 implement-queue-using-stacks javascript 📝 Easy 233 number-of-digit-one Hard 234 palindrome-linked-list javascript Easy 235 lowest-common-ancestor-of-a-binary-search-tree javascript Easy 236 lowest-common-ancestor-of-a-binary-tree Medium 237 delete-node-in-a-linked-list javascript 📝 Easy 238 product-of-array-except-self javascript Medium 239 sliding-window-maximum Hard 240 search-a-2d-matrix-ii javascript Medium 241 different-ways-to-add-parentheses Medium 242 valid-anagram javascript 📝 Easy 243 shortest-word-distance 🔒 📝 Easy 244 shortest-word-distance-ii 🔒 Medium 245 shortest-word-distance-iii 🔒 Medium 246 strobogrammatic-number 🔒 Easy 247 strobogrammatic-number-ii 🔒 Medium 248 strobogrammatic-number-iii 🔒 Hard 249 group-shifted-strings 🔒 Easy 250 count-univalue-subtrees 🔒 Medium 251 flatten-2d-vector 🔒 Medium 252 meeting-rooms 🔒 📝 Easy 253 meeting-rooms-ii 🔒 Medium 254 factor-combinations 🔒 Medium 255 verify-preorder-sequence-in-binary-search-tree 🔒 Medium 256 paint-house 🔒 Medium 257 binary-tree-paths Easy 258 add-digits javascript Easy 259 3sum-smaller 🔒 📝 Medium 260 single-number-iii javascript Medium 261 graph-valid-tree 🔒 Medium 263 ugly-number javascript Easy 264 ugly-number-ii Medium 265 paint-house-ii 🔒 Hard 266 palindrome-permutation 🔒 Easy 267 palindrome-permutation-ii 🔒 Medium 268 missing-number javascript Medium 269 alien-dictionary 🔒 Hard 270 closest-binary-search-tree-value 🔒 Easy 271 encode-and-decode-strings 🔒 Medium 272 closest-binary-search-tree-value-ii 🔒 Hard 273 integer-to-english-words Hard 274 h-index 📝 Medium 275 h-index-ii Medium 276 paint-fence 🔒 Easy 277 find-the-celebrity 🔒 Medium 278 first-bad-version javascript 📝 Easy 279 perfect-squares Medium 280 wiggle-sort 🔒 📝 Medium 281 zigzag-iterator 🔒 Medium 282 expression-add-operators Hard 283 move-zeroes javascript 📝 Easy 284 peeking-iterator Medium 285 inorder-successor-in-bst 🔒 Medium 286 walls-and-gates 🔒 📝 Medium 287 find-the-duplicate-number javascript Hard 288 unique-word-abbreviation 🔒 📝 Easy 289 game-of-life Medium 290 word-pattern javascript Easy 291 word-pattern-ii 🔒 Hard 292 nim-game javascript 📝 Easy 293 flip-game 🔒 Easy 294 flip-game-ii 🔒 Medium 295 find-median-from-data-stream Hard 296 best-meeting-point 🔒 📝 Hard 297 serialize-and-deserialize-binary-tree Hard 298 binary-tree-longest-consecutive-sequence 🔒 📝 Medium 299 bulls-and-cows javascript Easy 300 longest-increasing-subsequence Medium 301 remove-invalid-parentheses Hard 302 smallest-rectangle-enclosing-black-pixels 🔒 Hard 303 range-sum-query-immutable javascript 📝 Easy 304 range-sum-query-2d-immutable 📝 Medium 305 number-of-islands-ii 🔒 Hard 306 additive-number Medium 307 range-sum-query-mutable 📝 Medium 308 range-sum-query-2d-mutable 🔒 Hard 309 best-time-to-buy-and-sell-stock-with-cooldown Medium 310 minimum-height-trees Medium 311 sparse-matrix-multiplication 🔒 Medium 312 burst-balloons Hard 313 super-ugly-number Medium 314 binary-tree-vertical-order-traversal 🔒 Medium 315 count-of-smaller-numbers-after-self Hard 316 remove-duplicate-letters Hard 317 shortest-distance-from-all-buildings 🔒 Hard 318 maximum-product-of-word-lengths Medium 319 bulb-switcher javascript Medium 320 generalized-abbreviation 🔒 Medium 321 create-maximum-number Hard 322 coin-change 📝 Medium 323 number-of-connected-components-in-an-undirected-graph 🔒 Medium 324 wiggle-sort-ii Medium 325 maximum-size-subarray-sum-equals-k 🔒 Medium 326 power-of-three javascript 📝 Easy 327 count-of-range-sum Hard 328 odd-even-linked-list javascript 📝 Medium 329 longest-increasing-path-in-a-matrix Hard 330 patching-array Hard 331 verify-preorder-serialization-of-a-binary-tree Medium 332 reconstruct-itinerary Medium 333 largest-bst-subtree 🔒 Medium 334 increasing-triplet-subsequence Medium 335 self-crossing Hard 336 palindrome-pairs Hard 337 house-robber-iii Medium 338 counting-bits javascript Medium 339 nested-list-weight-sum 🔒 📝 Easy 340 longest-substring-with-at-most-k-distinct-characters 🔒 Hard 341 flatten-nested-list-iterator Medium 342 power-of-four javascript Easy 343 integer-break Medium 344 reverse-string javascript Easy 345 reverse-vowels-of-a-string javascript Easy 346 moving-average-from-data-stream 🔒 Easy 347 top-k-frequent-elements javascript Medium 348 design-tic-tac-toe 🔒 Medium 349 intersection-of-two-arrays javascript Easy 350 intersection-of-two-arrays-ii javascript Easy 351 android-unlock-patterns 🔒 📝 Medium 352 data-stream-as-disjoint-intervals Hard 353 design-snake-game 🔒 Medium 354 russian-doll-envelopes Hard 355 design-twitter Medium 356 line-reflection 🔒 Medium 357 count-numbers-with-unique-digits Medium 358 rearrange-string-k-distance-apart 🔒 Hard 359 logger-rate-limiter 🔒 Easy 360 sort-transformed-array 🔒 Medium 361 bomb-enemy 🔒 Medium 362 design-hit-counter 🔒 Medium 363 max-sum-of-sub-matrix-no-larger-than-k Hard 364 nested-list-weight-sum-ii 🔒 Medium 365 water-and-jug-problem Medium 366 find-leaves-of-binary-tree 🔒 Medium 367 valid-perfect-square Medium 368 largest-divisible-subset Medium 369 plus-one-linked-list 🔒 Medium 370 range-addition 🔒 📝 Medium 371 sum-of-two-integers javascript Easy 372 super-pow Medium 373 find-k-pairs-with-smallest-sums Medium 374 guess-number-higher-or-lower javascript 📝 Easy 375 guess-number-higher-or-lower-ii Medium 376 wiggle-subsequence 📝 Medium 377 combination-sum-iv Medium 378 kth-smallest-element-in-a-sorted-matrix Medium 379 design-phone-directory 🔒 Medium 380 insert-delete-getrandom-o1 Hard 381 insert-delete-getrandom-o1-duplicates-allowed Hard 382 linked-list-random-node Medium 383 ransom-note javascript Easy 384 shuffle-an-array Medium 385 mini-parser Medium 386 lexicographical-numbers Medium 387 first-unique-character-in-a-string javascript Easy 388 longest-absolute-file-path Medium 389 find-the-difference javascript Easy 390 elimination-game Medium 391 perfect-rectangle Hard 392 is-subsequence javascript Medium 393 utf-8-validation Medium 394 decode-string Medium 395 longest-substring-with-at-least-k-repeating-characters Medium 396 rotate-function javascript Easy 397 integer-replacement Medium 398 random-pick-index Medium 399 evaluate-division Medium 400 nth-digit javascript Easy 401 binary-watch javascript Easy 402 remove-k-digits Medium 403 frog-jump Hard 404 sum-of-left-leaves javascript Easy 405 convert-a-number-to-hexadecimal javascript Easy 406 queue-reconstruction-by-height Medium 407 trapping-rain-water-ii Hard 408 valid-word-abbreviation 🔒 Easy 409 longest-palindrome javascript Easy 410 split-array-largest-sum Hard 411 minimum-unique-word-abbreviation 🔒 Hard 412 fizz-buzz javascript Easy 413 arithmetic-slices Medium 414 third-maximum-number javascript Easy 415 add-strings javascript Easy 416 partition-equal-subset-sum Medium 417 pacific-atlantic-water-flow Medium 418 sentence-screen-fitting 🔒 Medium 419 battleships-in-a-board Medium 420 strong-password-checker Hard 421 maximum-xor-of-two-numbers-in-an-array Medium 422 valid-word-square 🔒 Easy 423 reconstruct-original-digits-from-english Medium 424 longest-repeating-character-replacement Medium 425 word-squares 🔒 Hard 432 all-oone-data-structure Hard 435 non-overlapping-intervals Medium 436 find-right-interval Medium 437 path-sum-iii Easy 438 find-all-anagrams-in-a-string Easy 439 ternary-expression-parser 🔒 Medium 440 k-th-smallest-in-lexicographical-order Hard 441 arranging-coins javascript Easy 444 sequence-reconstruction 🔒 Medium 446 arithmetic-slices-ii-subsequence Hard 447 number-of-boomerangs Easy 452 minimum-number-of-arrows-to-burst-balloons Medium 453 minimum-moves-to-equal-array-elements Easy 454 4sum-ii Medium 455 assign-cookies Easy 456 132-pattern Medium 459 repeated-substring-pattern Easy 462 minimum-moves-to-equal-array-elements-ii Medium 463 island-perimeter Easy 464 can-i-win Medium 465 optimal-account-balancing 🔒 Hard