Amazon
2015 problems
| Problem | Difficulty | Frequency ↓ | Topics |
|---|---|---|---|
| 609. Find Duplicate File in System | Medium | 13.2% | TopicsArrayHash TableString |
| 3356. Zero Array Transformation II | Medium | 13.2% | TopicsArrayTwo PointersBinary SearchPrefix Sum |
| 2484. Count Palindromic Subsequences | Hard | 13.2% | TopicsStringDynamic Programming |
| 2426. Number of Pairs Satisfying Inequality | Hard | 13.2% | TopicsArrayBinary SearchDivide and ConquerBinary Indexed TreeSegment TreeMerge SortOrdered Set |
| Expression Add Operators | Hard | 13.2% | TopicsMathStringBacktracking |
| Range Sum Query 2D - Mutable | Medium | 13.2% | TopicsArrayDesignBinary Indexed TreeSegment TreeMatrixSqrt Decomposition |
| 2894. Divisible and Non-divisible Sums Difference | Easy | 13.2% | TopicsMath |
| 1691. Maximum Height by Stacking Cuboids | Hard | 13.2% | TopicsArrayDynamic ProgrammingSorting |
| 637. Average of Levels in Binary Tree | Easy | 13.2% | TopicsTreeDepth-First SearchBreadth-First SearchBinary Tree |
| 3330. Find the Original Typed String I | Easy | 13.2% | TopicsString |
| 3333. Find the Original Typed String II | Hard | 13.2% | TopicsStringDynamic ProgrammingPrefix Sum |
| 821. Shortest Distance to a Character | Easy | 13.2% | TopicsArrayTwo PointersString |
| Number of Islands II | Hard | 13.2% | TopicsArrayHash TableUnion-Find |
| 3507. Minimum Pair Removal to Sort Array I | Easy | 13.2% | TopicsArrayHash TableLinked ListHeap (Priority Queue)SimulationDoubly-Linked ListOrdered Set |
| 2210. Count Hills and Valleys in an Array | Easy | 13.2% | TopicsArray |
| 2119. A Number After a Double Reversal | Easy | 13.2% | TopicsMath |
| 3479. Fruits Into Baskets III | Medium | 13.2% | TopicsArrayBinary SearchSegment TreeOrdered Set |
| 1504. Count Submatrices With All Ones | Medium | 13.2% | TopicsArrayDynamic ProgrammingStackMatrixMonotonic Stack |
| 1266. Minimum Time Visiting All Points | Easy | 13.2% | TopicsArrayMathGeometry |
| 3025. Find the Number of Ways to Place People I | Medium | 13.2% | TopicsArrayMathGeometrySortingEnumeration |
| 2749. Minimum Operations to Make the Integer Zero | Medium | 13.2% | TopicsBit ManipulationBrainteaserEnumeration |
| 1317. Convert Integer to the Sum of Two No-Zero Integers | Easy | 13.2% | TopicsMath |
| 3147. Taking Maximum Energy From the Mystic Dungeon | Medium | 13.2% | TopicsArrayDynamic ProgrammingPrefix Sum |
| 2598. Smallest Missing Non-negative Integer After Operations | Medium | 13.2% | TopicsArrayHash TableMathGreedy |
| 3397. Maximum Number of Distinct Elements After Operations | Medium | 13.2% | TopicsArrayGreedySorting |
