├── CONTRIBUTING.md ├── LICENSE └── README.md /CONTRIBUTING.md: -------------------------------------------------------------------------------- 1 | # A couple of things to keep in mind: 2 | - Just update in this format 3 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | MIT License 2 | 3 | Copyright (c) 2017 Bozhao(Joshua) Li 4 | 5 | Permission is hereby granted, free of charge, to any person obtaining a copy 6 | of this software and associated documentation files (the "Software"), to deal 7 | in the Software without restriction, including without limitation the rights 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 9 | copies of the Software, and to permit persons to whom the Software is 10 | furnished to do so, subject to the following conditions: 11 | 12 | The above copyright notice and this permission notice shall be included in all 13 | copies or substantial portions of the Software. 14 | 15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | 2 | # Information 3 | Right now I work in Google and would like to give reference for job application. Please send the CV to my email address bozhaoli.usc@gmail.com. 4 | Unsubscribed the Leetocode membership so this repo is valid until 04/2018 5 | # Leetcode Company Tag 6 | There is the collection of each company's tag questions on [Leetcode](https://leetcode.com/problemset/all/). 7 | Welcome to contribute other company's questions based on this format. 8 | # Table of Company 9 | To be Continue 10 | 11 | -[Facebook](#facebook) 12 | -[Google](#google) 13 | -[Uber](#uber) 14 | -[Bloomberg](#bloomberg) 15 | -[Microsoft](#microsoft) 16 | -[Amazon](#amazon) 17 | -[Linkedin](#linkedin) 18 | 19 | # Facebook 20 | Title | Acceptance | Difficulty | Frequency 21 | ---- | --- | --- | --- 22 | 534|Design TinyURL|0.0%|Medium| 23 | 283|Move Zeroes|50.7%|Easy| 24 | 301|Remove Invalid Parentheses|35.5%|Hard| 25 | 273|Integer to English Words|22.4%|Hard| 26 | 621|Task Scheduler|42.2%|Medium| 27 | 67|Add Binary|33.2%|Easy| 28 | 689|Maximum Sum of 3 Non-Overlapping Subarrays|41.3%|Hard| 29 | 325|Maximum Size Subarray Sum Equals k |43.0%|Medium| 30 | 253|Meeting Rooms II |39.3%|Medium| 31 | 17|Letter Combinations of a Phone Number|35.4%|Medium| 32 | 91|Decode Ways|20.0%|Medium| 33 | 311|Sparse Matrix Multiplication |51.8%|Medium| 34 | 314|Binary Tree Vertical Order Traversal |37.3%|Medium| 35 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 36 | 10|Regular Expression Matching|24.3%|Hard| 37 | 15|3Sum|21.8%|Medium| 38 | 158|Read N Characters Given Read4 II - Call multiple times |24.5%|Hard| 39 | 277|Find the Celebrity |35.6%|Medium| 40 | 278|First Bad Version|25.8%|Easy| 41 | 200|Number of Islands|35.6%|Medium| 42 | 76|Minimum Window Substring|26.1%|Hard| 43 | 257|Binary Tree Paths|39.7%|Easy| 44 | 543|Diameter of Binary Tree|44.7%|Easy| 45 | 157|Read N Characters Given Read4 |29.2%|Easy| 46 | 282|Expression Add Operators|30.2%|Hard| 47 | 23|Merge k Sorted Lists|27.7%|Hard| 48 | 173|Binary Search Tree Iterator|42.4%|Medium| 49 | 121|Best Time to Buy and Sell Stock|42.1%|Easy| 50 | 211|Add and Search Word - Data structure design|24.1%|Medium| 51 | 56|Merge Intervals|31.0%|Medium| 52 | 1|Two Sum|36.1%|Easy| 53 | 125|Valid Palindrome|26.6%|Easy| 54 | 161|One Edit Distance |31.6%|Medium| 55 | 597|Friend Requests I: Overall Acceptance Rate |37.3%|Easy| 56 | 252|Meeting Rooms |48.3%|Easy| 57 | 341|Flatten Nested List Iterator|42.2%|Medium| 58 | 285|Inorder Successor in BST |36.3%|Medium| 59 | 98|Validate Binary Search Tree|23.8%|Medium| 60 | 43|Multiply Strings|27.6%|Medium| 61 | 78|Subsets|42.5%|Medium| 62 | 602|Friend Requests II: Who Has the Most Friends |41.3%|Medium| 63 | 139|Word Break|30.8%|Medium| 64 | 670|Maximum Swap|38.3%|Medium| 65 | 57|Insert Interval|28.3%|Hard| 66 | 215|Kth Largest Element in an Array|39.9%|Medium| 67 | 75|Sort Colors|38.4%|Medium| 68 | 133|Clone Graph|25.1%|Medium| 69 | 680|Valid Palindrome II|32.2%|Easy| 70 | 33|Search in Rotated Sorted Array|32.0%|Medium| 71 | 238|Product of Array Except Self|49.8%|Medium| 72 | 636|Exclusive Time of Functions|43.9%|Medium| 73 | 88|Merge Sorted Array|32.1%|Easy| 74 | 206|Reverse Linked List|46.1%|Easy| 75 | 79|Word Search|27.4%|Medium| 76 | 13|Roman to Integer|46.8%|Easy| 77 | 236|Lowest Common Ancestor of a Binary Tree|30.0%|Medium| 78 | 146|LRU Cache|18.7%|Hard| 79 | 494|Target Sum|43.6%|Medium| 80 | 523|Continuous Subarray Sum|23.2%|Medium| 81 | 477|Total Hamming Distance|47.7%|Medium| 82 | 642|Design Search Autocomplete System |30.7%|Hard| 83 | 38|Count and Say|35.7%|Easy| 84 | 554|Brick Wall|46.1%|Medium| 85 | 398|Random Pick Index|43.9%|Medium| 86 | 218|The Skyline Problem|28.2%|Hard| 87 | 49|Group Anagrams|36.4%|Medium| 88 | 286|Walls and Gates |44.8%|Medium| 89 | 209|Minimum Size Subarray Sum|31.4%|Medium| 90 | 208|Implement Trie (Prefix Tree)|29.5%|Medium| 91 | 102|Binary Tree Level Order Traversal|41.0%|Medium| 92 | 71|Simplify Path|25.8%|Medium| 93 | 20|Valid Parentheses|33.7%|Easy| 94 | 28|Implement strStr()|28.6%|Easy| 95 | 90|Subsets II|37.2%|Medium| 96 | 128|Longest Consecutive Sequence|37.5%|Hard| 97 | 127|Word Ladder|19.7%|Medium| 98 | 377|Combination Sum IV|42.4%|Medium| 99 | 380|Insert Delete GetRandom O(1)|39.4%|Medium| 100 | 44|Wildcard Matching|20.6%|Hard| 101 | 334|Increasing Triplet Subsequence|39.8%|Medium| 102 | 269|Alien Dictionary |25.2%|Hard| 103 | 639|Decode Ways II|24.3%|Hard| 104 | 461|Hamming Distance|69.8%|Easy| 105 | 235|Lowest Common Ancestor of a Binary Search Tree|39.5%|Easy| 106 | 674|Longest Continuous Increasing Subsequence|42.9%|Easy| 107 | 647|Palindromic Substrings|55.7%|Medium| 108 | 117|Populating Next Right Pointers in Each Node II|33.8%|Medium| 109 | 50|Pow(x, n)|26.0%|Medium| 110 | 85|Maximal Rectangle|28.8%|Hard| 111 | 69|Sqrt(x)|28.2%|Easy| 112 | 68|Text Justification|19.6%|Hard| 113 | 210|Course Schedule II|29.1%|Medium| 114 | 26|Remove Duplicates from Sorted Array|35.5%|Easy| 115 | 221|Maximal Square|29.6%|Medium| 116 | 274|H-Index|33.5%|Medium| 117 | 404|Sum of Left Leaves|47.3%|Easy| 118 | 25|Reverse Nodes in k-Group|31.1%|Hard| 119 | 234|Palindrome Linked List|33.1%|Easy| 120 | 168|Excel Sheet Column Title|26.7%|Easy| 121 | 261|Graph Valid Tree |38.1%|Medium| 122 | 410|Split Array Largest Sum|38.6%|Hard| 123 | 525|Contiguous Array|40.9%|Medium| 124 | 535|Encode and Decode TinyURL|74.2%|Medium| 125 | 572|Subtree of Another Tree|40.6%|Easy| 126 | 265|Paint House II |38.1%|Hard| 127 | 714|Best Time to Buy and Sell Stock with Transaction Fee|39.4%|Medium| 128 | 578|Get Highest Answer Rate Question |28.1%|Medium| 129 | 637|Average of Levels in Binary Tree|55.6%|Easy| 130 | 721|Accounts Merge|27.4%|Medium| 131 | 653|Two Sum IV - Input is a BST|50.4%|Easy| 132 | 673|Number of Longest Increasing Subsequence|31.2%|Medium| 133 | 80|Remove Duplicates from Sorted Array II|36.4%|Medium| 134 | 275|H-Index II|34.7%|Medium| 135 | 136 | # Google 137 | Title | Acceptance | Difficulty | Frequency 138 | ---- | --- | --- | --- 139 | 534|Design TinyURL|0.0%|Medium| 140 | 388|Longest Absolute File Path|37.1%|Medium| 141 | 683|K Empty Slots |36.6%|Hard| 142 | 681|Next Closest Time |42.9%|Medium| 143 | 340|Longest Substring with At Most K Distinct Characters |39.2%|Hard| 144 | 482|License Key Formatting|41.8%|Medium| 145 | 308|Range Sum Query 2D - Mutable |24.1%|Hard| 146 | 346|Moving Average from Data Stream |59.5%|Easy| 147 | 298|Binary Tree Longest Consecutive Sequence |41.4%|Medium| 148 | 418|Sentence Screen Fitting |27.8%|Medium| 149 | 281|Zigzag Iterator |51.4%|Medium| 150 | 425|Word Squares |43.5%|Hard| 151 | 361|Bomb Enemy |39.4%|Medium| 152 | 394|Decode String|41.7%|Medium| 153 | 393|UTF-8 Validation|34.7%|Medium| 154 | 568|Maximum Vacation Days |39.1%|Hard| 155 | 163|Missing Ranges |23.8%|Medium| 156 | 66|Plus One|39.1%|Easy| 157 | 686|Repeated String Match|32.9%|Easy| 158 | 351|Android Unlock Patterns |44.3%|Medium| 159 | 317|Shortest Distance from All Buildings |34.4%|Hard| 160 | 271|Encode and Decode Strings |26.2%|Medium| 161 | 289|Game of Life|37.1%|Medium| 162 | 288|Unique Word Abbreviation |17.3%|Medium| 163 | 305|Number of Islands II |39.3%|Hard| 164 | 200|Number of Islands|35.6%|Medium| 165 | 280|Wiggle Sort |57.9%|Medium| 166 | 616|Add Bold Tag in String |38.7%|Medium| 167 | 259|3Sum Smaller |41.7%|Medium| 168 | 218|The Skyline Problem|28.2%|Hard| 169 | 399|Evaluate Division|41.5%|Medium| 170 | 159|Longest Substring with At Most Two Distinct Characters |41.9%|Hard| 171 | 246|Strobogrammatic Number |40.0%|Easy| 172 | 329|Longest Increasing Path in a Matrix|36.9%|Hard| 173 | 417|Pacific Atlantic Water Flow|34.1%|Medium| 174 | 406|Queue Reconstruction by Height|56.2%|Medium| 175 | 279|Perfect Squares|37.5%|Medium| 176 | 345|Reverse Vowels of a String|38.7%|Easy| 177 | 56|Merge Intervals|31.0%|Medium| 178 | 687|Longest Univalue Path|33.3%|Easy| 179 | 284|Peeking Iterator|35.5%|Medium| 180 | 247|Strobogrammatic Number II |40.5%|Medium| 181 | 524|Longest Word in Dictionary through Deleting|43.3%|Medium| 182 | 471|Encode String with Shortest Length |42.8%|Hard| 183 | 228|Summary Ranges|30.8%|Medium| 184 | 391|Perfect Rectangle|27.1%|Hard| 185 | 407|Trapping Rain Water II|37.6%|Hard| 186 | 286|Walls and Gates |44.8%|Medium| 187 | 362|Design Hit Counter |54.4%|Medium| 188 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 189 | 294|Flip Game II |46.6%|Medium| 190 | 146|LRU Cache|18.7%|Hard| 191 | 380|Insert Delete GetRandom O(1)|39.4%|Medium| 192 | 276|Paint Fence |34.7%|Easy| 193 | 401|Binary Watch|44.9%|Easy| 194 | 295|Find Median from Data Stream|28.0%|Hard| 195 | 249|Group Shifted Strings |42.7%|Medium| 196 | 463|Island Perimeter|57.5%|Easy| 197 | 42|Trapping Rain Water|37.2%|Hard| 198 | 320|Generalized Abbreviation |45.5%|Medium| 199 | 505|The Maze II |38.2%|Medium| 200 | 341|Flatten Nested List Iterator|42.2%|Medium| 201 | 266|Palindrome Permutation |57.5%|Easy| 202 | 315|Count of Smaller Numbers After Self|34.8%|Hard| 203 | 360|Sort Transformed Array |44.5%|Medium| 204 | 411|Minimum Unique Word Abbreviation |33.3%|Hard| 205 | 269|Alien Dictionary |25.2%|Hard| 206 | 239|Sliding Window Maximum|33.6%|Hard| 207 | 389|Find the Difference|51.0%|Easy| 208 | 465|Optimal Account Balancing |37.8%|Hard| 209 | 274|H-Index|33.5%|Medium| 210 | 253|Meeting Rooms II |39.3%|Medium| 211 | 128|Longest Consecutive Sequence|37.5%|Hard| 212 | 20|Valid Parentheses|33.7%|Easy| 213 | 158|Read N Characters Given Read4 II - Call multiple times |24.5%|Hard| 214 | 293|Flip Game |56.5%|Easy| 215 | 139|Word Break|30.8%|Medium| 216 | 415|Add Strings|41.5%|Easy| 217 | 359|Logger Rate Limiter |60.1%|Easy| 218 | 230|Kth Smallest Element in a BST|44.5%|Medium| 219 | 162|Find Peak Element|38.1%|Medium| 220 | 270|Closest Binary Search Tree Value |40.1%|Easy| 221 | 23|Merge k Sorted Lists|27.7%|Hard| 222 | 498|Diagonal Traverse|46.1%|Medium| 223 | 400|Nth Digit|30.1%|Easy| 224 | 490|The Maze |43.2%|Medium| 225 | 318|Maximum Product of Word Lengths|44.9%|Medium| 226 | 10|Regular Expression Matching|24.3%|Hard| 227 | 212|Word Search II|24.0%|Hard| 228 | 240|Search a 2D Matrix II|38.8%|Medium| 229 | 373|Find K Pairs with Smallest Sums|30.9%|Medium| 230 | 4|Median of Two Sorted Arrays|22.3%|Hard| 231 | 369|Plus One Linked List |54.8%|Medium| 232 | 422|Valid Word Square |36.4%|Easy| 233 | 251|Flatten 2D Vector |40.9%|Medium| 234 | 332|Reconstruct Itinerary|29.4%|Medium| 235 | 173|Binary Search Tree Iterator|42.4%|Medium| 236 | 155|Min Stack|29.7%|Easy| 237 | 358|Rearrange String k Distance Apart |31.7%|Hard| 238 | 54|Spiral Matrix|26.6%|Medium| 239 | 587|Erect the Fence|32.6%|Hard| 240 | 679|24 Game|38.9%|Hard| 241 | 140|Word Break II|23.9%|Hard| 242 | 324|Wiggle Sort II|26.2%|Medium| 243 | 17|Letter Combinations of a Phone Number|35.4%|Medium| 244 | 484|Find Permutation |55.1%|Medium| 245 | 562|Longest Line of Consecutive One in Matrix |40.9%|Medium| 246 | 166|Fraction to Recurring Decimal|17.8%|Medium| 247 | 22|Generate Parentheses|46.3%|Medium| 248 | 409|Longest Palindrome|45.5%|Easy| 249 | 224|Basic Calculator|27.8%|Hard| 250 | 31|Next Permutation|28.8%|Medium| 251 | 676|Implement Magic Dictionary|50.0%|Medium| 252 | 327|Count of Range Sum|30.1%|Hard| 253 | 421|Maximum XOR of Two Numbers in an Array|46.9%|Medium| 254 | 57|Insert Interval|28.3%|Hard| 255 | 503|Next Greater Element II|47.3%|Medium| 256 | 336|Palindrome Pairs|26.6%|Hard| 257 | 684|Redundant Connection|39.2%|Medium| 258 | 133|Clone Graph|25.1%|Medium| 259 | 44|Wildcard Matching|20.6%|Hard| 260 | 50|Pow(x, n)|26.0%|Medium| 261 | 543|Diameter of Binary Tree|44.7%|Easy| 262 | 460|LFU Cache|24.4%|Hard| 263 | 231|Power of Two|40.4%|Easy| 264 | 208|Implement Trie (Prefix Tree)|29.5%|Medium| 265 | 363|Max Sum of Rectangle No Larger Than K|33.4%|Hard| 266 | 354|Russian Doll Envelopes|32.3%|Hard| 267 | 348|Design Tic-Tac-Toe |45.8%|Medium| 268 | 652|Find Duplicate Subtrees|35.8%|Medium| 269 | 444|Sequence Reconstruction |19.6%|Medium| 270 | 309|Best Time to Buy and Sell Stock with Cooldown|41.3%|Medium| 271 | 501|Find Mode in Binary Search Tree|37.7%|Easy| 272 | 382|Linked List Random Node|47.1%|Medium| 273 | 402|Remove K Digits|26.0%|Medium| 274 | 370|Range Addition |56.5%|Medium| 275 | 272|Closest Binary Search Tree Value II |39.4%|Hard| 276 | 475|Heaters|29.6%|Easy| 277 | 214|Shortest Palindrome|24.7%|Hard| 278 | 551|Student Attendance Record I|44.1%|Easy| 279 | 377|Combination Sum IV|42.4%|Medium| 280 | 282|Expression Add Operators|30.2%|Hard| 281 | 302|Smallest Rectangle Enclosing Black Pixels |45.9%|Hard| 282 | 379|Design Phone Directory |34.1%|Medium| 283 | 353|Design Snake Game |26.8%|Medium| 284 | 375|Guess Number Higher or Lower II|35.9%|Medium| 285 | 459|Repeated Substring Pattern|38.2%|Easy| 286 | 356|Line Reflection |30.1%|Medium| 287 | 261|Graph Valid Tree |38.1%|Medium| 288 | 486|Predict the Winner|45.1%|Medium| 289 | 542|01 Matrix|33.0%|Medium| 290 | 397|Integer Replacement|30.2%|Medium| 291 | 321|Create Maximum Number|24.8%|Hard| 292 | 408|Valid Word Abbreviation |28.2%|Easy| 293 | 368|Largest Divisible Subset|33.7%|Medium| 294 | 378|Kth Smallest Element in a Sorted Matrix|45.2%|Medium| 295 | 530|Minimum Absolute Difference in BST|47.1%|Easy| 296 | 313|Super Ugly Number|38.0%|Medium| 297 | 331|Verify Preorder Serialization of a Binary Tree|36.6%|Medium| 298 | 323|Number of Connected Components in an Undirected Graph |48.3%|Medium| 299 | 451|Sort Characters By Frequency|51.1%|Medium| 300 | 374|Guess Number Higher or Lower|35.9%|Easy| 301 | 448|Find All Numbers Disappeared in an Array|51.2%|Easy| 302 | 310|Minimum Height Trees|28.9%|Medium| 303 | 326|Power of Three|40.4%|Easy| 304 | 257|Binary Tree Paths|39.7%|Easy| 305 | 520|Detect Capital|51.9%|Easy| 306 | 729|My Calendar I|36.1%|Medium| 307 | 469|Convex Polygon |33.4%|Medium| 308 | 474|Ones and Zeroes|39.1%|Medium| 309 | 480|Sliding Window Median|31.1%|Hard| 310 | 481|Magical String|45.6%|Medium| 311 | 483|Smallest Good Base|33.4%|Hard| 312 | 485|Max Consecutive Ones|54.0%|Easy| 313 | 312|Burst Balloons|43.2%|Hard| 314 | 314|Binary Tree Vertical Order Traversal |37.3%|Medium| 315 | 357|Count Numbers with Unique Digits|46.1%|Medium| 316 | 487|Max Consecutive Ones II |45.6%|Medium| 317 | 493|Reverse Pairs|20.6%|Hard| 318 | 494|Target Sum|43.6%|Medium| 319 | 506|Relative Ranks|46.6%|Easy| 320 | 514|Freedom Trail|39.1%|Hard| 321 | 447|Number of Boomerangs|45.7%|Easy| 322 | 521|Longest Uncommon Subsequence I|55.9%|Easy| 323 | 522|Longest Uncommon Subsequence II|31.8%|Medium| 324 | 526|Beautiful Arrangement|54.2%|Medium| 325 | 527|Word Abbreviation |41.9%|Hard| 326 | 316|Remove Duplicate Letters|29.9%|Hard| 327 | 531|Lonely Pixel I |55.6%|Medium| 328 | 533|Lonely Pixel II |44.6%|Medium| 329 | 535|Encode and Decode TinyURL|74.2%|Medium| 330 | 541|Reverse String II|43.7%|Easy| 331 | 330|Patching Array|32.3%|Hard| 332 | 544|Output Contest Matches |70.9%|Medium| 333 | 545|Boundary of Binary Tree |31.9%|Medium| 334 | 549|Binary Tree Longest Consecutive Sequence II |41.9%|Medium| 335 | 552|Student Attendance Record II|31.3%|Hard| 336 | 560|Subarray Sum Equals K|40.4%|Medium| 337 | 569|Median Employee Salary |34.2%|Hard| 338 | 581|Shortest Unsorted Continuous Subarray|29.3%|Easy| 339 | 583|Delete Operation for Two Strings|44.2%|Medium| 340 | 604|Design Compressed String Iterator |32.5%|Easy| 341 | 638|Shopping Offers|43.4%|Medium| 342 | 643|Maximum Average Subarray I|37.8%|Easy| 343 | 644|Maximum Average Subarray II |23.0%|Hard| 344 | 651|4 Keys Keyboard |48.8%|Medium| 345 | 656|Coin Path |25.1%|Hard| 346 | 657|Judge Route Circle|68.6%|Easy| 347 | 658|Find K Closest Elements|35.3%|Medium| 348 | 659|Split Array into Consecutive Subsequences|35.7%|Medium| 349 | 665|Non-decreasing Array|21.1%|Easy| 350 | 667|Beautiful Arrangement II|51.5%|Medium| 351 | 668|Kth Smallest Number in Multiplication Table|37.7%|Hard| 352 | 685|Redundant Connection II|28.4%|Hard| 353 | 689|Maximum Sum of 3 Non-Overlapping Subarrays|41.3%|Hard| 354 | 719|Find K-th Smallest Pair Distance|25.3%|Hard| 355 | 726|Number of Atoms|45.7%|Hard| 356 | 727|Minimum Window Subsequence |29.1%|Hard| 357 | 731|My Calendar II|31.6%|Medium 358 | 359 | # Uber 360 | Title | Acceptance | Difficulty | Frequency 361 | ---- | --- | --- | --- 362 | 534|Design TinyURL|0.0%|Medium| 363 | 380|Insert Delete GetRandom O(1)|39.4%|Medium| 364 | 291|Word Pattern II |38.1%|Hard| 365 | 262|Trips and Users|18.1%|Hard| 366 | 254|Factor Combinations |43.2%|Medium| 367 | 36|Valid Sudoku|36.5%|Medium| 368 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 369 | 636|Exclusive Time of Functions|43.9%|Medium| 370 | 139|Word Break|30.8%|Medium| 371 | 432|All O`one Data Structure|28.1%|Hard| 372 | 146|LRU Cache|18.7%|Hard| 373 | 692|Top K Frequent Words|40.6%|Medium| 374 | 17|Letter Combinations of a Phone Number|35.4%|Medium| 375 | 49|Group Anagrams|36.4%|Medium| 376 | 648|Replace Words|47.3%|Medium| 377 | 249|Group Shifted Strings |42.7%|Medium| 378 | 22|Generate Parentheses|46.3%|Medium| 379 | 54|Spiral Matrix|26.6%|Medium| 380 | 133|Clone Graph|25.1%|Medium| 381 | 535|Encode and Decode TinyURL|74.2%|Medium| 382 | 290|Word Pattern|33.2%|Easy| 383 | 13|Roman to Integer|46.8%|Easy| 384 | 450|Delete Node in a BST|37.2%|Medium| 385 | 10|Regular Expression Matching|24.3%|Hard| 386 | 186|Reverse Words in a String II |27.7%|Medium| 387 | 208|Implement Trie (Prefix Tree)|29.5%|Medium| 388 | 37|Sudoku Solver|31.0%|Hard| 389 | 140|Word Break II|23.9%|Hard| 390 | 39|Combination Sum|39.9%|Medium| 391 | 138|Copy List with Random Pointer|26.1%|Medium| 392 | 23|Merge k Sorted Lists|27.7%|Hard| 393 | 207|Course Schedule|32.8%|Medium| 394 | 230|Kth Smallest Element in a BST|44.5%|Medium| 395 | 1|Two Sum|36.1%|Easy| 396 | 91|Decode Ways|20.0%|Medium| 397 | 78|Subsets|42.5%|Medium| 398 | 337|House Robber III|44.0%|Medium| 399 | 33|Search in Rotated Sorted Array|32.0%|Medium| 400 | 161|One Edit Distance |31.6%|Medium| 401 | 242|Valid Anagram|46.9%|Easy| 402 | 76|Minimum Window Substring|26.1%|Hard| 403 | 24|Swap Nodes in Pairs|38.7%|Medium| 404 | 202|Happy Number|41.1%|Easy| 405 | 206|Reverse Linked List|46.1%|Easy| 406 | 155|Min Stack|29.7%|Easy| 407 | 121|Best Time to Buy and Sell Stock|42.1%|Easy| 408 | 125|Valid Palindrome|26.6%|Easy| 409 | 373|Find K Pairs with Smallest Sums|30.9%|Medium| 410 | 266|Palindrome Permutation |57.5%|Easy| 411 | 104|Maximum Depth of Binary Tree|53.4%|Easy| 412 | 699|Falling Squares|36.5%|Hard| 413 | 690|Employee Importance|52.9%|Easy| 414 | 516|Longest Palindromic Subsequence|42.6%|Medium| 415 | 8|String to Integer (atoi)|13.9%|Medium| 416 | 171|Excel Sheet Column Number|47.7%|Easy| 417 | 418 | 419 | # Bloomberg 420 | Title | Acceptance | Difficulty | Frequency 421 | ---- | --- | --- | --- 422 | 445|Add Two Numbers II|45.9%|Medium| 423 | 138|Copy List with Random Pointer|26.1%|Medium| 424 | 582|Kill Process |49.8%|Medium| 425 | 121|Best Time to Buy and Sell Stock|42.1%|Easy| 426 | 692|Top K Frequent Words|40.6%|Medium| 427 | 387|First Unique Character in a String|47.1%|Easy| 428 | 1|Two Sum|36.1%|Easy| 429 | 117|Populating Next Right Pointers in Each Node II|33.8%|Medium| 430 | 283|Move Zeroes|50.7%|Easy| 431 | 155|Min Stack|29.7%|Easy| 432 | 20|Valid Parentheses|33.7%|Easy| 433 | 56|Merge Intervals|31.0%|Medium| 434 | 146|LRU Cache|18.7%|Hard| 435 | 42|Trapping Rain Water|37.2%|Hard| 436 | 206|Reverse Linked List|46.1%|Easy| 437 | 122|Best Time to Buy and Sell Stock II|47.6%|Easy| 438 | 50|Pow(x, n)|26.0%|Medium| 439 | 2|Add Two Numbers|28.1%|Medium| 440 | 69|Sqrt(x)|28.2%|Easy| 441 | 62|Unique Paths|41.9%|Medium| 442 | 98|Validate Binary Search Tree|23.8%|Medium| 443 | 160|Intersection of Two Linked Lists|30.8%|Easy| 444 | 268|Missing Number|44.3%|Easy| 445 | 53|Maximum Subarray|39.9%|Easy| 446 | 78|Subsets|42.5%|Medium| 447 | 232|Implement Queue using Stacks|37.4%|Easy| 448 | 7|Reverse Integer|24.4%|Easy| 449 | 287|Find the Duplicate Number|43.8%|Medium| 450 | 215|Kth Largest Element in an Array|39.9%|Medium| 451 | 49|Group Anagrams|36.4%|Medium| 452 | 386|Lexicographical Numbers|41.8%|Medium| 453 | 151|Reverse Words in a String|15.7%|Medium| 454 | 139|Word Break|30.8%|Medium| 455 | 102|Binary Tree Level Order Traversal|41.0%|Medium| 456 | 103|Binary Tree Zigzag Level Order Traversal|35.5%|Medium| 457 | 88|Merge Sorted Array|32.1%|Easy| 458 | 3|Longest Substring Without Repeating Characters|24.5%|Medium| 459 | 208|Implement Trie (Prefix Tree)|29.5%|Medium| 460 | 225|Implement Stack using Queues|33.5%|Easy| 461 | 105|Construct Binary Tree from Preorder and Inorder Traversal|32.8%|Medium| 462 | 141|Linked List Cycle|35.3%|Easy| 463 | 230|Kth Smallest Element in a BST|44.5%|Medium| 464 | 5|Longest Palindromic Substring|25.3%|Medium| 465 | 26|Remove Duplicates from Sorted Array|35.5%|Easy| 466 | 33|Search in Rotated Sorted Array|32.0%|Medium| 467 | 13|Roman to Integer|46.8%|Easy| 468 | 8|String to Integer (atoi)|13.9%|Medium| 469 | 63|Unique Paths II|32.0%|Medium| 470 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 471 | 172|Factorial Trailing Zeroes|36.5%|Easy| 472 | 101|Symmetric Tree|39.5%|Easy| 473 | 79|Word Search|27.4%|Medium| 474 | 100|Same Tree|47.0%|Easy| 475 | 189|Rotate Array|25.0%|Easy| 476 | 15|3Sum|21.8%|Medium| 477 | 110|Balanced Binary Tree|37.9%|Easy| 478 | 547|Friend Circles|49.2%|Medium| 479 | 113|Path Sum II|34.5%|Medium| 480 | 24|Swap Nodes in Pairs|38.7%|Medium| 481 | 443|String Compression|37.1%|Easy| 482 | 16|3Sum Closest|31.3%|Medium| 483 | 266|Palindrome Permutation |57.5%|Easy| 484 | 556|Next Greater Element III|28.9%|Medium| 485 | 11|Container With Most Water|36.8%|Medium| 486 | 158|Read N Characters Given Read4 II - Call multiple times |24.5%|Hard| 487 | 570|Managers with at Least 5 Direct Reports |54.3%|Medium| 488 | 131|Palindrome Partitioning|34.4%|Medium| 489 | 274|H-Index|33.5%|Medium| 490 | 669|Trim a Binary Search Tree|57.8%|Easy| 491 | 714|Best Time to Buy and Sell Stock with Transaction Fee|39.4%|Medium 492 | 493 | # Microsoft 494 | Title | Acceptance | Difficulty | Frequency 495 | ---- | --- | --- | --- 496 | 138|Copy List with Random Pointer|26.1%|Medium| 497 | 348|Design Tic-Tac-Toe |45.8%|Medium| 498 | 206|Reverse Linked List|46.1%|Easy| 499 | 419|Battleships in a Board|62.3%|Medium| 500 | 273|Integer to English Words|22.4%|Hard| 501 | 171|Excel Sheet Column Number|47.7%|Easy| 502 | 54|Spiral Matrix|26.6%|Medium| 503 | 186|Reverse Words in a String II |27.7%|Medium| 504 | 88|Merge Sorted Array|32.1%|Easy| 505 | 445|Add Two Numbers II|45.9%|Medium| 506 | 235|Lowest Common Ancestor of a Binary Search Tree|39.5%|Easy| 507 | 1|Two Sum|36.1%|Easy| 508 | 53|Maximum Subarray|39.9%|Easy| 509 | 236|Lowest Common Ancestor of a Binary Tree|30.0%|Medium| 510 | 200|Number of Islands|35.6%|Medium| 511 | 21|Merge Two Sorted Lists|39.3%|Easy| 512 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 513 | 103|Binary Tree Zigzag Level Order Traversal|35.5%|Medium| 514 | 218|The Skyline Problem|28.2%|Hard| 515 | 116|Populating Next Right Pointers in Each Node|36.9%|Medium| 516 | 73|Set Matrix Zeroes|36.2%|Medium| 517 | 117|Populating Next Right Pointers in Each Node II|33.8%|Medium| 518 | 151|Reverse Words in a String|15.7%|Medium| 519 | 121|Best Time to Buy and Sell Stock|42.1%|Easy| 520 | 13|Roman to Integer|46.8%|Easy| 521 | 48|Rotate Image|40.0%|Medium| 522 | 75|Sort Colors|38.4%|Medium| 523 | 268|Missing Number|44.3%|Easy| 524 | 20|Valid Parentheses|33.7%|Easy| 525 | 141|Linked List Cycle|35.3%|Easy| 526 | 2|Add Two Numbers|28.1%|Medium| 527 | 238|Product of Array Except Self|49.8%|Medium| 528 | 8|String to Integer (atoi)|13.9%|Medium| 529 | 24|Swap Nodes in Pairs|38.7%|Medium| 530 | 5|Longest Palindromic Substring|25.3%|Medium| 531 | 33|Search in Rotated Sorted Array|32.0%|Medium| 532 | 146|LRU Cache|18.7%|Hard| 533 | 98|Validate Binary Search Tree|23.8%|Medium| 534 | 168|Excel Sheet Column Title|26.7%|Easy| 535 | 153|Find Minimum in Rotated Sorted Array|40.3%|Medium| 536 | 237|Delete Node in a Linked List|47.0%|Easy| 537 | 208|Implement Trie (Prefix Tree)|29.5%|Medium| 538 | 232|Implement Queue using Stacks|37.4%|Easy| 539 | 173|Binary Search Tree Iterator|42.4%|Medium| 540 | 160|Intersection of Two Linked Lists|30.8%|Easy| 541 | 4|Median of Two Sorted Arrays|22.3%|Hard| 542 | 26|Remove Duplicates from Sorted Array|35.5%|Easy| 543 | 174|Dungeon Game|23.9%|Hard| 544 | 212|Word Search II|24.0%|Hard| 545 | 102|Binary Tree Level Order Traversal|41.0%|Medium| 546 | 23|Merge k Sorted Lists|27.7%|Hard| 547 | 285|Inorder Successor in BST |36.3%|Medium| 548 | 191|Number of 1 Bits|39.9%|Easy| 549 | 106|Construct Binary Tree from Inorder and Postorder Traversal|32.6%|Medium| 550 | 25|Reverse Nodes in k-Group|31.1%|Hard| 551 | 215|Kth Largest Element in an Array|39.9%|Medium| 552 | 189|Rotate Array|25.0%|Easy| 553 | 71|Simplify Path|25.8%|Medium| 554 | 387|First Unique Character in a String|47.1%|Easy| 555 | 15|3Sum|21.8%|Medium| 556 | 567|Permutation in String|36.6%|Medium| 557 | 94|Binary Tree Inorder Traversal|47.8%|Medium| 558 | 204|Count Primes|26.6%|Easy| 559 | 46|Permutations|45.3%|Medium| 560 | 56|Merge Intervals|31.0%|Medium| 561 | 28|Implement strStr()|28.6%|Easy| 562 | 124|Binary Tree Maximum Path Sum|26.6%|Hard| 563 | 101|Symmetric Tree|39.5%|Easy| 564 | 165|Compare Version Numbers|20.4%|Medium| 565 | 91|Decode Ways|20.0%|Medium| 566 | 300|Longest Increasing Subsequence|38.7%|Medium| 567 | 114|Flatten Binary Tree to Linked List|35.7%|Medium| 568 | 270|Closest Binary Search Tree Value |40.1%|Easy| 569 | 79|Word Search|27.4%|Medium| 570 | 125|Valid Palindrome|26.6%|Easy| 571 | 162|Find Peak Element|38.1%|Medium| 572 | 258|Add Digits|51.5%|Easy| 573 | 112|Path Sum|34.4%|Easy| 574 | 55|Jump Game|29.5%|Medium| 575 | 513|Find Bottom Left Tree Value|56.1%|Medium| 576 | 672|Bulb Switcher II|47.9%|Medium| 577 | 722|Remove Comments|25.8%|Medium| 578 | 365|Water and Jug Problem|27.7%|Medium| 579 | 443|String Compression|37.1%|Easy| 580 | 452|Minimum Number of Arrows to Burst Balloons|44.4%|Medium| 581 | 591|Tag Validator|30.1%|Hard| 582 | 631|Design Excel Sum Formula |27.6%|Hard| 583 | 47|Permutations II|33.7%|Medium| 584 | 642|Design Search Autocomplete System |30.7%|Hard| 585 | 650|2 Keys Keyboard|44.5%|Medium| 586 | 651|4 Keys Keyboard |48.8%|Medium| 587 | 213|House Robber II|34.3%|Medium| 588 | 654|Maximum Binary Tree|69.9%|Medium| 589 | 333|Largest BST Subtree |30.6%|Medium| 590 | 591 | # Amazon 592 | Title | Acceptance | Difficulty | Frequency 593 | ---- | --- | --- | --- 594 | 534|Design TinyURL|0.0%|Medium| 595 | 675|Cut Off Trees for Golf Event|26.6%|Hard| 596 | 1|Two Sum|36.1%|Easy| 597 | 20|Valid Parentheses|33.7%|Easy| 598 | 146|LRU Cache|18.7%|Hard| 599 | 711|Number of Distinct Islands II |37.7%|Hard| 600 | 200|Number of Islands|35.6%|Medium| 601 | 48|Rotate Image|40.0%|Medium| 602 | 438|Find All Anagrams in a String|33.8%|Easy| 603 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 604 | 138|Copy List with Random Pointer|26.1%|Medium| 605 | 236|Lowest Common Ancestor of a Binary Tree|30.0%|Medium| 606 | 5|Longest Palindromic Substring|25.3%|Medium| 607 | 239|Sliding Window Maximum|33.6%|Hard| 608 | 460|LFU Cache|24.4%|Hard| 609 | 121|Best Time to Buy and Sell Stock|42.1%|Easy| 610 | 17|Letter Combinations of a Phone Number|35.4%|Medium| 611 | 387|First Unique Character in a String|47.1%|Easy| 612 | 42|Trapping Rain Water|37.2%|Hard| 613 | 238|Product of Array Except Self|49.8%|Medium| 614 | 127|Word Ladder|19.7%|Medium| 615 | 23|Merge k Sorted Lists|27.7%|Hard| 616 | 682|Baseball Game|58.7%|Easy| 617 | 206|Reverse Linked List|46.1%|Easy| 618 | 235|Lowest Common Ancestor of a Binary Search Tree|39.5%|Easy| 619 | 380|Insert Delete GetRandom O(1)|39.4%|Medium| 620 | 2|Add Two Numbers|28.1%|Medium| 621 | 234|Palindrome Linked List|33.1%|Easy| 622 | 449|Serialize and Deserialize BST|42.4%|Medium| 623 | 155|Min Stack|29.7%|Easy| 624 | 240|Search a 2D Matrix II|38.8%|Medium| 625 | 98|Validate Binary Search Tree|23.8%|Medium| 626 | 21|Merge Two Sorted Lists|39.3%|Easy| 627 | 139|Word Break|30.8%|Medium| 628 | 215|Kth Largest Element in an Array|39.9%|Medium| 629 | 49|Group Anagrams|36.4%|Medium| 630 | 517|Super Washing Machines|36.5%|Hard| 631 | 126|Word Ladder II|14.5%|Hard| 632 | 3|Longest Substring Without Repeating Characters|24.5%|Medium| 633 | 242|Valid Anagram|46.9%|Easy| 634 | 160|Intersection of Two Linked Lists|30.8%|Easy| 635 | 141|Linked List Cycle|35.3%|Easy| 636 | 529|Minesweeper|49.4%|Medium| 637 | 186|Reverse Words in a String II |27.7%|Medium| 638 | 167|Two Sum II - Input array is sorted|47.2%|Easy| 639 | 15|3Sum|21.8%|Medium| 640 | 102|Binary Tree Level Order Traversal|41.0%|Medium| 641 | 78|Subsets|42.5%|Medium| 642 | 545|Boundary of Binary Tree |31.9%|Medium| 643 | 516|Longest Palindromic Subsequence|42.6%|Medium| 644 | 73|Set Matrix Zeroes|36.2%|Medium| 645 | 535|Encode and Decode TinyURL|74.2%|Medium| 646 | 199|Binary Tree Right Side View|41.6%|Medium| 647 | 8|String to Integer (atoi)|13.9%|Medium| 648 | 508|Most Frequent Subtree Sum|52.2%|Medium| 649 | 204|Count Primes|26.6%|Easy| 650 | 538|Convert BST to Greater Tree|49.1%|Easy| 651 | 89|Gray Code|41.7%|Medium| 652 | 414|Third Maximum Number|28.0%|Easy| 653 | 189|Rotate Array|25.0%|Easy| 654 | 451|Sort Characters By Frequency|51.1%|Medium| 655 | 355|Design Twitter|25.6%|Medium| 656 | 532|K-diff Pairs in an Array|28.2%|Easy| 657 | 119|Pascal's Triangle II|37.5%|Easy| 658 | 606|Construct String from Binary Tree|49.7%|Easy| 659 | 617|Merge Two Binary Trees|67.6%|Easy| 660 | 645|Set Mismatch|40.0%|Easy| 661 | 537|Complex Number Multiplication|64.0%|Medium| 662 | 646|Maximum Length of Pair Chain|47.7%|Medium| 663 | 662|Maximum Width of Binary Tree|38.1%|Medium| 664 | 396|Rotate Function|33.4%|Medium| 665 | 536|Construct Binary Tree from String |42.8%|Medium| 666 | 663|Equal Tree Partition |36.6%|Medium| 667 | 692|Top K Frequent Words|40.6%|Medium| 668 | 459|Repeated Substring Pattern|38.2%|Easy| 669 | 579|Find Cumulative Salary of an Employee |27.0%|Hard| 670 | 553|Optimal Division|55.2%|Medium| 671 | 694|Number of Distinct Islands |43.8%|Medium| 672 | 661|Image Smoother|45.9%|Easy| 673 | 640|Solve the Equation|38.9%|Medium| 674 | 725|Split Linked List in Parts|49.6%|Medium 675 | 676 | # Linkedin 677 | Title | Acceptance | Difficulty | Frequency 678 | ---- | --- | --- | --- 679 | 339|Nested List Weight Sum |62.8%|Easy| 680 | 244|Shortest Word Distance II |39.5%|Medium| 681 | 364|Nested List Weight Sum II |53.2%|Medium| 682 | 170|Two Sum III - Data structure design |25.4%|Easy| 683 | 256|Paint House |46.2%|Easy| 684 | 243|Shortest Word Distance |52.9%|Easy| 685 | 156|Binary Tree Upside Down |45.1%|Medium| 686 | 366|Find Leaves of Binary Tree |60.3%|Medium| 687 | 716|Max Stack |32.7%|Easy| 688 | 254|Factor Combinations |43.2%|Medium| 689 | 245|Shortest Word Distance III |50.8%|Medium| 690 | 205|Isomorphic Strings|34.3%|Easy| 691 | 53|Maximum Subarray|39.9%|Easy| 692 | 297|Serialize and Deserialize Binary Tree|34.0%|Hard| 693 | 605|Can Place Flowers|30.1%|Easy| 694 | 698|Partition to K Equal Sum Subsets|36.9%|Medium| 695 | 50|Pow(x, n)|26.0%|Medium| 696 | 65|Valid Number|12.8%|Hard| 697 | 149|Max Points on a Line|15.2%|Hard| 698 | 68|Text Justification|19.6%|Hard| 699 | 277|Find the Celebrity |35.6%|Medium| 700 | 56|Merge Intervals|31.0%|Medium| 701 | 102|Binary Tree Level Order Traversal|41.0%|Medium| 702 | 236|Lowest Common Ancestor of a Binary Tree|30.0%|Medium| 703 | 152|Maximum Product Subarray|26.2%|Medium| 704 | 187|Repeated DNA Sequences|32.2%|Medium| 705 | 1|Two Sum|36.1%|Easy| 706 | 34|Search for a Range|31.4%|Medium| 707 | 311|Sparse Matrix Multiplication |51.8%|Medium| 708 | 150|Evaluate Reverse Polish Notation|27.7%|Medium| 709 | 464|Can I Win|25.2%|Medium| 710 | 33|Search in Rotated Sorted Array|32.0%|Medium| 711 | 46|Permutations|45.3%|Medium| 712 | 76|Minimum Window Substring|26.1%|Hard| 713 | 104|Maximum Depth of Binary Tree|53.4%|Easy| 714 | 238|Product of Array Except Self|49.8%|Medium| 715 | 127|Word Ladder|19.7%|Medium| 716 | 101|Symmetric Tree|39.5%|Easy| 717 | 57|Insert Interval|28.3%|Hard| 718 | 103|Binary Tree Zigzag Level Order Traversal|35.5%|Medium| 719 | 198|House Robber|39.4%|Easy| 720 | 23|Merge k Sorted Lists|27.7%|Hard| 721 | 21|Merge Two Sorted Lists|39.3%|Easy| 722 | 47|Permutations II|33.7%|Medium| 723 | 515|Find Largest Value in Each Tree Row|55.1%|Medium| 724 | 173|Binary Search Tree Iterator|42.4%|Medium| 725 | 633|Sum of Square Numbers|32.3%|Easy| 726 | 647|Palindromic Substrings|55.7%|Medium| 727 | 671|Second Minimum Node In a Binary Tree|41.9%|Easy| 728 | 367|Valid Perfect Square|38.5%|Easy| 729 | 730|Count Different Palindromic Subsequences|25.4%|Hard 730 | 731 | 732 | --------------------------------------------------------------------------------