Amazon
2015 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| 1372. Longest ZigZag Path in a Binary Tree | Medium | 7.2% | TopicsDynamic ProgrammingTreeDepth-First SearchBinary TreeDP on Trees |
| 1477. Find Two Non-overlapping Sub-arrays Each With Target Sum | Medium | 7.2% | TopicsArrayHash TableBinary SearchDynamic ProgrammingSliding Window |
| 3498. Reverse Degree of a String | Easy | 7.2% | TopicsStringSimulation |
| 4068. Maximize Meeting Earnings with Idle Gaps | Hard | 7.2% | TopicsArrayBinary SearchDynamic ProgrammingSorting |
| 2267. Check if There Is a Valid Parentheses String Path | Hard | 7.2% | TopicsArrayDynamic ProgrammingMatrixBracket Sequences |
| Longest Substring with At Most Two Distinct Characters | Medium | 5% | TopicsHash TableStringSliding Window |
| Maximum Size Subarray Sum Equals k | Medium | 5% | TopicsArrayHash TablePrefix Sum |
| Longest Absolute File Path | Medium | 5% | TopicsStringStackDepth-First Search |
| Convert a Number to Hexadecimal | Easy | 5% | TopicsMathStringBit Manipulation |
| Hamming Distance | Easy | 5% | TopicsBit Manipulation |
| Magical String | Medium | 5% | TopicsTwo PointersString |
| Beautiful Arrangement | Medium | 5% | TopicsArrayDynamic ProgrammingBacktrackingBit ManipulationBitmask |
| Delete Operation for Two Strings | Medium | 5% | TopicsStringDynamic ProgrammingLongest Common Subsequence |
| Shopping Offers | Medium | 5% | TopicsArrayDynamic ProgrammingBacktrackingBit ManipulationMemoizationBitmaskKnapsack ProblemComplete Knapsack |
| My Calendar II | Medium | 5% | TopicsArrayBinary SearchDesignSegment TreePrefix SumOrdered Set |
| Convert Binary Search Tree to Sorted Doubly Linked List | Medium | 5% | TopicsLinked ListStackTreeDepth-First SearchBinary Search TreeBinary TreeDoubly-Linked List |
| 784. Letter Case Permutation | Medium | 5% | TopicsStringBacktrackingBit Manipulation |
| 834. Sum of Distances in Tree | Hard | 5% | TopicsDynamic ProgrammingTreeDepth-First SearchGraph TheoryDP on Trees |
| 839. Similar String Groups | Hard | 5% | TopicsArrayHash TableStringDepth-First SearchBreadth-First SearchUnion-Find |
| 845. Longest Mountain in Array | Medium | 5% | TopicsArrayTwo PointersDynamic ProgrammingEnumeration |
| 880. Decoded String at Index | Medium | 5% | TopicsStringStack |
| 897. Increasing Order Search Tree | Easy | 5% | TopicsStackTreeDepth-First SearchBinary Search TreeBinary Tree |
| 910. Smallest Range II | Medium | 5% | TopicsArrayMathGreedySorting |
| 932. Beautiful Array | Medium | 5% | TopicsArrayMathDivide and Conquer |
| 995. Minimum Number of K Consecutive Bit Flips | Hard | 5% | TopicsArrayBit ManipulationQueueSliding WindowPrefix SumBrute-Force Search |
