Amazon
2015 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| Valid Number | Hard | 25.2% | TopicsString |
| Minimum Depth of Binary Tree | Easy | 25.2% | TopicsTreeDepth-First SearchBreadth-First SearchBinary Tree |
| Number of Digit One | Hard | 25.2% | TopicsMathDynamic ProgrammingRecursion |
| Different Ways to Add Parentheses | Medium | 25.2% | TopicsMathStringDynamic ProgrammingRecursionMemoizationBracket Sequences |
| Single Number III | Medium | 25.2% | TopicsArrayBit Manipulation |
| 263. Ugly Number | Easy | 25.2% | TopicsMath |
| Binary Tree Vertical Order Traversal | Medium | 25.2% | TopicsHash TableTreeDepth-First SearchBreadth-First SearchSortingBinary Tree |
| Insert Delete GetRandom O(1) - Duplicates allowed | Hard | 25.2% | TopicsArrayHash TableMathDesignRandomized |
| Longest Palindrome | Easy | 25.2% | TopicsHash TableStringGreedy |
| 433. Minimum Genetic Mutation | Medium | 25.2% | TopicsHash TableStringBreadth-First SearchBidirectional Search |
| Serialize and Deserialize BST | Medium | 25.2% | TopicsStringTreeDepth-First SearchBreadth-First SearchDesignBinary Search TreeBinary Tree |
| Valid Triangle Number | Medium | 25.2% | TopicsArrayTwo PointersBinary SearchGreedySorting |
| Course Schedule III | Hard | 25.2% | TopicsArrayGreedySortingHeap (Priority Queue) |
| Cut Off Trees for Golf Event | Hard | 25.2% | TopicsArrayBreadth-First SearchHeap (Priority Queue)Matrix |
| 890. Find and Replace Pattern | Medium | 25.2% | TopicsArrayHash TableString |
| 895. Maximum Frequency Stack | Hard | 25.2% | TopicsHash TableStackDesignOrdered Set |
| 899. Orderly Queue | Hard | 25.2% | TopicsMathStringSortingLexicographically Minimal String Rotation |
| 980. Unique Paths III | Hard | 25.2% | TopicsArrayBacktrackingBit ManipulationMatrixHamiltonian Path |
| 1002. Find Common Characters | Easy | 25.2% | TopicsArrayHash TableString |
| 1022. Sum of Root To Leaf Binary Numbers | Easy | 25.2% | TopicsTreeDepth-First SearchBinary Tree |
| 1026. Maximum Difference Between Node and Ancestor | Medium | 25.2% | TopicsTreeDepth-First SearchBinary Tree |
| 1035. Uncrossed Lines | Medium | 25.2% | TopicsArrayDynamic ProgrammingLongest Common Subsequence |
| 1092. Shortest Common Supersequence | Hard | 25.2% | TopicsStringDynamic ProgrammingLongest Common Subsequence |
| 1315. Sum of Nodes with Even-Valued Grandparent | Medium | 25.2% | TopicsTreeDepth-First SearchBreadth-First SearchBinary Tree |
| 1146. Snapshot Array | Medium | 25.2% | TopicsArrayHash TableBinary SearchDesignPersistent Data Structure |
