Amazon
2015 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| Palindrome Partitioning II | Hard | 30.3% | TopicsStringDynamic Programming |
| 165. Compare Version Numbers | Medium | 30.3% | TopicsTwo PointersString |
| 191. Number of 1 Bits | Easy | 30.3% | TopicsDivide and ConquerBit Manipulation |
| 228. Summary Ranges | Easy | 30.3% | TopicsArray |
| 332. Reconstruct Itinerary | Hard | 30.3% | TopicsArrayStringDepth-First SearchGraph TheorySortingHeap (Priority Queue)Eulerian CircuitEulerian PathSemi-Eulerian Graph |
| Add Strings | Easy | 30.3% | TopicsMathStringSimulation |
| Super Washing Machines | Hard | 30.3% | TopicsArrayGreedy |
| 523. Continuous Subarray Sum | Medium | 30.3% | TopicsArrayHash TableMathPrefix SumPigeonhole Principle |
| Triangle Judgement | Easy | 30.3% | TopicsDatabase |
| Flatten a Multilevel Doubly Linked List | Medium | 30.3% | TopicsLinked ListDepth-First SearchDoubly-Linked List |
| 862. Shortest Subarray with Sum at Least K | Hard | 30.3% | TopicsArrayBinary SearchQueueSliding WindowHeap (Priority Queue)Prefix SumMonotonic Queue |
| 918. Maximum Sum Circular Subarray | Medium | 30.3% | TopicsArrayDivide and ConquerDynamic ProgrammingQueueMonotonic Queue |
| 1038. Binary Search Tree to Greater Sum Tree | Medium | 30.3% | TopicsTreeDepth-First SearchBinary Search TreeBinary Tree |
| 1046. Last Stone Weight | Easy | 30.3% | TopicsArrayHeap (Priority Queue) |
| 1365. How Many Numbers Are Smaller Than the Current Number | Easy | 30.3% | TopicsArrayHash TableSortingCounting Sort |
| 1478. Allocate Mailboxes | Hard | 30.3% | TopicsArrayMathDynamic ProgrammingSorting |
| 1472. Design Browser History | Medium | 30.3% | TopicsArrayLinked ListStackDesignDoubly-Linked ListData Stream |
| 1700. Number of Students Unable to Eat Lunch | Easy | 30.3% | TopicsArrayStackQueueSimulation |
| 2390. Removing Stars From a String | Medium | 30.3% | TopicsStringStackSimulation |
| 2434. Using a Robot to Print the Lexicographically Smallest String | Medium | 30.3% | TopicsHash TableStringStackGreedy |
| 2929. Distribute Candies Among Children II | Medium | 30.3% | TopicsMathCombinatoricsEnumeration |
| 2488. Count Subarrays With Median K | Hard | 30.3% | TopicsArrayHash TablePrefix Sum |
| 113. Path Sum II | Medium | 29.1% | TopicsBacktrackingTreeDepth-First SearchBinary Tree |
| Repeated DNA Sequences | Medium | 29.1% | TopicsHash TableStringBit ManipulationSliding WindowRolling HashHash FunctionZ AlgorithmBoyer–Moore String-Search Algorithm |
| Combination Sum III | Medium | 29.1% | TopicsArrayBacktracking |
