Questions by Companies Google # Title Acceptance Difficulty 1 Two Sum 45.50% Easy 560 Subarray Sum Equals K 43.90% Medium 68 Text Justification 27.50% Hard 253 Meeting Rooms II 45.60% Medium 76 Minimum Window Substring 34.40% Hard 85 Maximal Rectangle 37.40% Hard 221 Maximal Square 37.60% Medium 127 Word Ladder 29.20% Medium 295 Find Median from Data Stream 43.90% Hard 394 Decode String 49.60% Medium 362 Design Hit Counter 63.40% Medium 528 Random Pick with Weight 43.90% Medium 843 Guess the Word 46.00% Hard 1048 Longest String Chain 54.50% Medium 329 Longest Increasing Path in a Matrix 43.20% Hard 315 Count of Smaller Numbers After Self 41.40% Hard 642 Design Search Autocomplete System 44.40% Hard 410 Split Array Largest Sum 44.40% Hard 359 Logger Rate Limiter 70.30% Easy 593 Valid Square 42.90% Medium 946 Validate Stack Sequences 61.40% Medium 1153 String Transforms Into Another String 35.90% Hard 727 Minimum Window Subsequence 41.50% Hard 399 Evaluate Division 51.30% Medium 1110 Delete Nodes And Return Forest 66.70% Medium 722 Remove Comments 34.30% Medium 809 Expressive Words 47.20% Medium 729 My Calendar I 51.50% Medium 1031 Maximum Sum of Two Non-Overlapping Subarrays 57.70% Medium 752 Open the Lock 51.50% Medium 679 24 Game 46.10% Hard 489 Robot Room Cleaner 69.40% Hard 1146 Snapshot Array 37.00% Medium 862 Shortest Subarray with Sum at Least K 24.40% Hard 846 Hand of Straights 53.90% Medium 659 Split Array into Consecutive Subsequences 43.60% Medium 346 Moving Average from Data Stream 70.70% Easy 1438 Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit 42.60% Medium 1088 Confusing Number II 43.50% Hard 299 Bulls and Cows 42.30% Easy 951 Flip Equivalent Binary Trees 65.70% Medium 1376 Time Needed to Inform All Employees 55.20% Medium 1231 Divide Chocolate 52.20% Hard 1296 Divide Array in Sets of K Consecutive Numbers 53.20% Medium 375 Guess Number Higher or Lower II 40.20% Medium 1140 Stone Game II 62.80% Medium 1423 Maximum Points You Can Obtain from Cards 41.30% Medium 833 Find And Replace in String 50.30% Medium 1345 Jump Game IV 37.40% Hard 1463 Cherry Pickup II 64.50% Hard Amazon # Title Acceptance Difficulty 1 Two Sum 45.50% Easy 200 Number of Islands 46.50% Medium 2 Add Two Numbers 33.70% Medium 937 Reorder Data in Log Files 54.30% Easy 42 Trapping Rain Water 48.50% Hard 146 LRU Cache 32.80% Medium 5 Longest Palindromic Substring 29.30% Medium 23 Merge k Sorted Lists 39.90% Hard 1192 Critical Connections in a Network 48.60% Hard 21 Merge Two Sorted Lists 53.20% Easy 994 Rotting Oranges 47.60% Medium 56 Merge Intervals 39.10% Medium 273 Integer to English Words 26.90% Hard 121 Best Time to Buy and Sell Stock 50.30% Easy 692 Top K Frequent Words 51.50% Medium 269 Alien Dictionary 33.30% Hard 973 K Closest Points to Origin 63.60% Medium 139 Word Break 39.80% Medium 253 Meeting Rooms II 45.60% Medium 297 Serialize and Deserialize Binary Tree 47.10% Hard 49 Group Anagrams 56.40% Medium 763 Partition Labels 75.60% Medium 127 Word Ladder 29.20% Medium 138 Copy List with Random Pointer 35.80% Medium 295 Find Median from Data Stream 43.90% Hard 140 Word Break II 31.50% Hard 227 Basic Calculator II 36.70% Medium 79 Word Search 34.90% Medium 588 Design In-Memory File System 45.30% Hard 460 LFU Cache 33.90% Hard 239 Sliding Window Maximum 42.80% Hard 348 Design Tic-Tac-Toe 54.00% Medium 472 Concatenated Words 43.30% Hard 1152 Analyze User Website Visit Pattern 43.60% Medium 819 Most Common Word 44.60% Easy 211 Add and Search Word - Data structure design 36.60% Medium 126 Word Ladder II 21.90% Hard 240 Search a 2D Matrix II 43.10% Medium 210 Course Schedule II 39.70% Medium 642 Design Search Autocomplete System 44.40% Hard 480 Sliding Window Median 37.00% Hard 863 All Nodes Distance K in Binary Tree 55.00% Medium 733 Flood Fill 55.10% Easy 353 Design Snake Game 33.90% Medium 694 Number of Distinct Islands 55.70% Medium 909 Snakes and Ladders 38.30% Medium 564 Find the Closest Palindrome 19.60% Hard 1268 Search Suggestions System 63.30% Medium 1167 Minimum Cost to Connect Sticks 62.60% Medium 726 Number of Atoms 48.50% Hard Facebook # Title Acceptance Difficulty 23 Merge k Sorted Lists 39.90% Hard 238 Product of Array Except Self 59.90% Medium 56 Merge Intervals 39.10% Medium 273 Integer to English Words 26.90% Hard 953 Verifying an Alien Dictionary 54.30% Easy 560 Subarray Sum Equals K 43.90% Medium 1249 Minimum Remove to Make Valid Parentheses 62.40% Medium 269 Alien Dictionary 33.30% Hard 973 K Closest Points to Origin 63.60% Medium 31 Next Permutation 32.50% Medium 415 Add Strings 47.30% Easy 297 Serialize and Deserialize Binary Tree 47.10% Hard 88 Merge Sorted Array 39.20% Easy 215 Kth Largest Element in an Array 54.90% Medium 199 Binary Tree Right Side View 53.70% Medium 124 Binary Tree Maximum Path Sum 34.10% Hard 680 Valid Palindrome II 36.50% Easy 301 Remove Invalid Parentheses 43.10% Hard 986 Interval List Intersections 67.20% Medium 173 Binary Search Tree Iterator 56.10% Medium 987 Vertical Order Traversal of a Binary Tree 35.40% Medium 236 Lowest Common Ancestor of a Binary Tree 45.20% Medium 67 Add Binary 44.10% Easy 543 Diameter of Binary Tree 48.30% Easy 528 Random Pick with Weight 43.90% Medium 438 Find All Anagrams in a String 43.00% Medium 767 Reorganize String 48.30% Medium 211 Add and Search Word - Data structure design 36.60% Medium 158 Read N Characters Given Read4 II - Call multiple times 33.30% Hard 125 Valid Palindrome 35.80% Easy 636 Exclusive Time of Functions 51.80% Medium 340 Longest Substring with At Most K Distinct Characters 43.90% Hard 621 Task Scheduler 48.60% Medium 311 Sparse Matrix Multiplication 61.50% Medium 523 Continuous Subarray Sum 24.60% Medium 65 Valid Number 15.20% Hard 278 First Bad Version 35.40% Easy 721 Accounts Merge 48.30% Medium 938 Range Sum of BST 81.10% Easy 785 Is Graph Bipartite? 47.20% Medium 282 Expression Add Operators 35.40% Hard 270 Closest Binary Search Tree Value 47.80% Easy 1060 Missing Element in Sorted Array 54.40% Medium 670 Maximum Swap 43.30% Medium 249 Group Shifted Strings 54.50% Medium 1428 Leftmost Column with at Least a One 46.50% Medium 398 Random Pick Index 55.50% Medium 689 Maximum Sum of 3 Non-Overlapping Subarrays 46.00% Hard 896 Monotonic Array 57.70% Easy 1026 Maximum Difference Between Node and Ancestor 65.50% Medium LinkedIn # Title Acceptance Difficulty 53 Maximum Subarray 46.40% Easy 297 Serialize and Deserialize Binary Tree 47.10% Hard 380 Insert Delete GetRandom O(1) 47.40% Medium 127 Word Ladder 29.20% Medium 364 Nested List Weight Sum II 62.60% Medium 150 Evaluate Reverse Polish Notation 36.10% Medium 102 Binary Tree Level Order Traversal 54.20% Medium 698 Partition to K Equal Sum Subsets 45.00% Medium 101 Symmetric Tree 46.60% Easy 339 Nested List Weight Sum 73.60% Easy 716 Max Stack 42.50% Easy 149 Max Points on a Line 16.90% Hard 244 Shortest Word Distance II 52.20% Medium 605 Can Place Flowers 31.60% Easy 272 Closest Binary Search Tree Value II 50.30% Hard 254 Factor Combinations 46.60% Medium 244 Shortest Word Distance II 48.20% Medium 364 Nested List Weight Sum II 58.40% Medium 170 Two Sum III - Data structure design 31.00% Easy 339 Nested List Weight Sum 69.00% Easy 272 Closest Binary Search Tree Value II 45.80% Hard 156 Binary Tree Upside Down 51.60% Medium 256 Paint House 49.40% Easy 243 Shortest Word Distance 57.90% Easy 149 Max Points on a Line 16.00% Hard 265 Paint House II 42.00% Hard 65 Valid Number 14.20% Hard 716 Max Stack 40.40% Easy 254 Factor Combinations 44.70% Medium 380 Insert Delete GetRandom O(1) 43.30% Medium 68 Text Justification 23.90% Hard 366 Find Leaves of Binary Tree 66.50% Medium 605 Can Place Flowers 31.10% Easy Microsoft # Title Acceptance Difficulty 1246 Palindrome Removal 45.90% Hard 1239 Maximum Length of a Concatenated String with Unique Characters 47.60% Medium 273 Integer to English Words 26.90% Hard 428 Serialize and Deserialize N-ary Tree 59.00% Hard 146 LRU Cache 32.80% Medium 1156 Swap For Longest Repeated Character Substring 48.70% Medium 54 Spiral Matrix 33.90% Medium 212 Word Search II 34.50% Hard 1236 Web Crawler 64.30% Medium 828 Count Unique Characters of All Substrings of a Given String 44.80% Hard 138 Copy List with Random Pointer 35.80% Medium 545 Boundary of Binary Tree 38.90% Medium 25 Reverse Nodes in k-Group 41.70% Hard 348 Design Tic-Tac-Toe 54.00% Medium 450 Delete Node in a BST 42.90% Medium 124 Binary Tree Maximum Path Sum 34.10% Hard 340 Longest Substring with At Most K Distinct Characters 43.90% Hard 218 The Skyline Problem 34.40% Hard 200 Number of Islands 46.50% Medium 358 Rearrange String k Distance Apart 34.70% Hard 1375 Bulb Switcher III 62.10% Medium 99 Recover Binary Search Tree 39.30% Hard 468 Validate IP Address 24.00% Medium 116 Populating Next Right Pointers in Each Node 44.60% Medium 41 First Missing Positive 31.80% Hard 93 Restore IP Addresses 35.30% Medium 23 Merge k Sorted Lists 39.90% Hard 103 Binary Tree Zigzag Level Order Traversal 47.00% Medium 232 Implement Queue using Stacks 49.10% Easy 1 Two Sum 45.50% Easy 79 Word Search 34.90% Medium 1116 Print Zero Even Odd 55.70% Medium 297 Serialize and Deserialize Binary Tree 47.10% Hard 4 Median of Two Sorted Arrays 29.40% Hard 134 Gas Station 38.20% Medium 207 Course Schedule 42.80% Medium 445 Add Two Numbers II 54.30% Medium 105 Construct Binary Tree from Preorder and Inorder Traversal 48.20% Medium 42 Trapping Rain Water 48.50% Hard 74 Search a 2D Matrix 36.40% Medium 151 Reverse Words in a String 21.10% Medium 102 Binary Tree Level Order Traversal 54.20% Medium 10 Regular Expression Matching 26.70% Hard 173 Binary Search Tree Iterator 56.10% Medium 140 Word Break II 31.50% Hard 443 String Compression 41.00% Easy 8 String to Integer (atoi) 15.30% Medium 148 Sort List 41.80% Medium 630 Course Schedule III 33.30% Hard 155 Min Stack 44.20% Easy 621 Task Scheduler 48.60% Medium 432 All O`one Data Structure 32.20% Hard 285 Inorder Successor in BST 40.00% Medium 240 Search a 2D Matrix II 43.10% Medium 636 Exclusive Time of Functions 51.80% Medium 510 Inorder Successor in BST II 57.90% Medium 716 Max Stack 42.50% Easy 179 Largest Number 28.50% Medium 85 Maximal Rectangle 37.40% Hard 295 Find Median from Data Stream 43.90% Hard 46 Permutations 63.00% Medium 133 Clone Graph 34.20% Medium 89 Gray Code 48.90% Medium 622 Design Circular Queue 43.50% Medium 127 Word Ladder 29.20% Medium 126 Word Ladder II 21.90% Hard 37 Sudoku Solver 43.20% Hard 253 Meeting Rooms II 45.60% Medium 236 Lowest Common Ancestor of a Binary Tree 45.20% Medium 346 Moving Average from Data Stream 70.70% Easy 767 Reorganize String 48.30% Medium 706 Design HashMap 60.90% Easy 460 LFU Cache 33.90% Hard 277 Find the Celebrity 41.60% Medium 419 Battleships in a Board 69.80% Medium 695 Max Area of Island 62.40% Medium 48 Rotate Image 56.20% Medium 722 Remove Comments 34.30% Medium 380 Insert Delete GetRandom O(1) 47.40% Medium 75 Sort Colors 47.10% Medium 457 Circular Array Loop 29.20% Medium 557 Reverse Words in a String III 69.50% Easy 49 Group Anagrams 56.40% Medium 98 Validate Binary Search Tree 27.70% Medium 679 24 Game 46.10% Hard 1044 Longest Duplicate Substring 32.00% Hard 950 Reveal Cards In Increasing Order 74.30% Medium 128 Longest Consecutive Sequence 44.90% Hard 56 Merge Intervals 39.10% Medium 43 Multiply Strings 33.70% Medium 681 Next Closest Time 44.90% Medium 1229 Meeting Scheduler 52.30% Medium 149 Max Points on a Line 16.90% Hard 121 Best Time to Buy and Sell Stock 50.30% Easy 21 Merge Two Sorted Lists 53.20% Easy 17 Letter Combinations of a Phone Number 46.50% Medium 24 Swap Nodes in Pairs 50.00% Medium 33 Search in Rotated Sorted Array 34.50% Medium 773 Sliding Puzzle 59.00% Hard 129 Sum Root to Leaf Numbers 48.70% Medium 238 Product of Array Except Self 59.90% Medium 77 Combinations 54.30% Medium 528 Random Pick with Weight 43.90% Medium 53 Maximum Subarray 46.40% Easy Uber # Title Acceptance Difficulty 757 Set Intersection Size At Least Two 41.30% Hard 267 Palindrome Permutation II 36.80% Medium 529 Minesweeper 60.10% Medium 773 Sliding Puzzle 60.10% Hard 936 Stamping The Sequence 46.40% Hard 427 Construct Quad Tree 61.90% Medium 655 Print Binary Tree 55.30% Medium 305 Number of Islands II 39.90% Hard 1281 Subtract the Product and Sum of Digits of an Integer 85.50% Easy 1136 Parallel Courses 61.00% Hard 332 Reconstruct Itinerary 37.20% Medium 986 Interval List Intersections 67.70% Medium 465 Optimal Account Balancing 47.50% Hard 291 Word Pattern II 43.80% Hard 1368 Minimum Cost to Make at Least One Valid Path in a Grid 55.60% Hard 741 Cherry Pickup 34.50% Hard 527 Word Abbreviation 55.40% Hard 341 Flatten Nested List Iterator 53.60% Medium 68 Text Justification 28.50% Hard 34 Find First and Last Position of Element in Sorted Array 36.70% Medium 772 Basic Calculator III 42.30% Hard 56 Merge Intervals 39.90% Medium 1278 Palindrome Partitioning III 60.10% Hard 126 Word Ladder II 22.90% Hard 1400 Construct K Palindrome Strings 61.90% Medium 128 Longest Consecutive Sequence 45.60% Hard 361 Bomb Enemy 46.30% Medium 239 Sliding Window Maximum 44.00% Hard 752 Open the Lock 52.20% Medium 49 Group Anagrams 58.10% Medium 642 Design Search Autocomplete System 45.40% Hard 85 Maximal Rectangle 38.60% Hard 1227 Airplane Seat Assignment Probability 61.70% Medium 1135 Connecting Cities With Minimum Cost 58.50% Medium 130 Surrounded Regions 28.70% Medium 780 Reaching Points 29.90% Hard 1188 Design Bounded Blocking Queue 71.70% Medium 146 LRU Cache 34.40% Medium 297 Serialize and Deserialize Binary Tree 48.60% Hard 679 24 Game 46.90% Hard 716 Max Stack 42.70% Easy 445 Add Two Numbers II 55.20% Medium 855 Exam Room 43.40% Medium 279 Perfect Squares 48.10% Medium 315 Count of Smaller Numbers After Self 42.20% Hard 36 Valid Sudoku 49.60% Medium 353 Design Snake Game 34.80% Medium 863 All Nodes Distance K in Binary Tree 56.70% Medium 221 Maximal Square 38.10% Medium 871 Minimum Number of Refueling Stops 31.80% Hard 200 Number of Islands 47.70% Medium 380 Insert Delete GetRandom O(1) 48.10% Medium 3 Longest Substring Without Repeating Characters 30.80% Medium 23 Merge k Sorted Lists 41.30% Hard 53 Maximum Subarray 47.10% Easy 2 Add Two Numbers 34.50% Medium 399 Evaluate Division 53.50% Medium 273 Integer to English Words 27.60% Hard 969 Pancake Sorting 68.30% Medium 1229 Meeting Scheduler 53.60% Medium 992 Subarrays with K Different Integers 49.80% Hard 238 Product of Array Except Self 60.80% Medium 359 Logger Rate Limiter 71.40% Easy 1 Two Sum 46.00% Easy 628 Maximum Product of Three Numbers 47.00% Easy 621 Task Scheduler 50.90% Medium 428 Serialize and Deserialize N-ary Tree 60.40% Hard 227 Basic Calculator II 37.50% Medium 149 Max Points on a Line 17.10% Hard 438 Find All Anagrams in a String 44.10% Medium 311 Sparse Matrix Multiplication 62.90% Medium 979 Distribute Coins in Binary Tree 69.20% Medium 694 Number of Distinct Islands 56.70% Medium 262 Trips and Users 34.30% Hard 269 Alien Dictionary 33.40% Hard 395 Longest Substring with At Least K Repeating Characters 41.80% Medium 17 Letter Combinations of a Phone Number 47.80% Medium 729 My Calendar I 52.60% Medium 1038 Binary Search Tree to Greater Sum Tree 81.40% Medium 581 Shortest Unsorted Continuous Subarray 31.30% Medium 72 Edit Distance 45.80% Hard 977 Squares of a Sorted Array 72.10% Easy 166 Fraction to Recurring Decimal 22.00% Medium 282 Expression Add Operators 36.10% Hard 140 Word Break II 33.60% Hard 57 Insert Interval 34.50% Medium 4 Median of Two Sorted Arrays 30.30% Hard 124 Binary Tree Maximum Path Sum 34.90% Hard 50 Pow(x, n) 30.60% Medium 39 Combination Sum 58.00% Medium 426 Convert Binary Search Tree to Sorted Doubly Linked List 60.00% Medium 253 Meeting Rooms II 46.20% Medium 289 Game of Life 55.80% Medium 981 Time Based Key-Value Store 53.60% Medium 337 House Robber III 51.00% Medium 334 Increasing Triplet Subsequence 39.90% Medium 692 Top K Frequent Words 52.50% Medium 46 Permutations 65.00% Medium 42 Trapping Rain Water 50.00% Hard 210 Course Schedule II 41.60% Medium 131 Palindrome Partitioning 49.00% Medium 134 Gas Station 40.40% Medium 451 Sort Characters By Frequency 63.70% Medium 528 Random Pick with Weight 44.30% Medium 20 Valid Parentheses 39.30% Easy 121 Best Time to Buy and Sell Stock 51.10% Easy 70 Climbing Stairs 48.20% Easy 31 Next Permutation 33.00% Medium 852 Peak Index in a Mountain Array 71.80% Easy 767 Reorganize String 49.40% Medium 75 Sort Colors 48.30% Medium 211 Design Add and Search Words Data Structure 39.00% Medium 22 Generate Parentheses 64.00% Medium 208 Implement Trie (Prefix Tree) 50.70% Medium 173 Binary Search Tree Iterator 58.00% Medium 32 Longest Valid Parentheses 28.80% Hard 1143 Longest Common Subsequence 58.50% Medium 84 Largest Rectangle in Histogram 35.90% Hard 295 Find Median from Data Stream 45.60% Hard 16 3Sum Closest 46.10% Medium 215 Kth Largest Element in an Array 56.70% Medium 6 ZigZag Conversion 37.10% Medium 13 Roman to Integer 56.20% Easy 10 Regular Expression Matching 27.00% Hard 41 First Missing Positive 33.00% Hard 118 Pascal's Triangle 53.70% Easy 76 Minimum Window Substring 35.30% Hard 152 Maximum Product Subarray 32.40% Medium 127 Word Ladder 30.50% Medium 54 Spiral Matrix 34.70% Medium 74 Search a 2D Matrix 37.10% Medium 207 Course Schedule 43.70% Medium 62 Unique Paths 55.00% Medium 99 Recover Binary Search Tree 41.60% Hard 48 Rotate Image 58.30% Medium 15 3Sum 27.40% Medium 69 Sqrt(x) 34.50% Easy 5 Longest Palindromic Substring 29.80% Medium 973 K Closest Points to Origin 64.20% Medium 300 Longest Increasing Subsequence 42.90% Medium 21 Merge Two Sorted Lists 54.60% Easy 139 Word Break 40.90% Medium 234 Palindrome Linked List 39.80% Easy 560 Subarray Sum Equals K 43.80% Medium 242 Valid Anagram 57.60% Easy 228 Summary Ranges 41.60% Easy 322 Coin Change 36.40% Medium 198 House Robber 42.50% Easy 122 Best Time to Buy and Sell Stock II 57.80% Easy 1480 Running Sum of 1d Array 89.70% Easy 133 Clone Graph 37.30% Medium 104 Maximum Depth of Binary Tree 66.80% Easy 26 Remove Duplicates from Sorted Array 45.90% Easy 7 Reverse Integer 25.80% Easy Note: Refer individual folder for more details.