Problems
Callback's own problems and the LeetCode questions companies have been asking, in one place — filter by category, company, topic, difficulty, and how recently a question showed up.
Asked on LeetCode
2,011 questions at Amazon · all time
- Gray CodemediumMathBacktrackingBit Manipulationfrequency 32.3
- H-IndexmediumArraySortingCounting Sortfrequency 32.3
- Longest Arithmetic Sequence After Changing At Most One ElementmediumArrayEnumerationfrequency 32.3
- Maximum Number of Groups With Increasing LengthhardArrayMathBinary SearchGreedy+1frequency 32.3
- Minimum Number of Refueling StopshardArrayDynamic ProgrammingGreedyHeap (Priority Queue)frequency 32.3
- Next Greater Element IIImediumMathTwo PointersStringfrequency 32.3
- Partition Array According to Given PivotmediumArrayTwo PointersSimulationfrequency 32.3
- Removing Stars From a StringmediumStringStackSimulationfrequency 32.3
- Reorder Data in Log FilesmediumArrayStringSortingfrequency 32.3
- Sell Diminishing-Valued Colored BallsmediumArrayMathBinary SearchGreedy+2frequency 32.3
- Shuffle the ArrayeasyArrayfrequency 32.3
- Third Maximum NumbereasyArraySortingfrequency 32.3
- 132 PatternmediumArrayBinary SearchStackMonotonic Stack+1frequency 31.3
- Angle Between Hands of a ClockmediumMathfrequency 31.3
- Binary Search Tree to Greater Sum TreemediumTreeDepth-First SearchBinary Search TreeBinary Treefrequency 31.3
- Binary Subarrays With SummediumArrayHash TableSliding WindowPrefix Sumfrequency 31.3
- Boundary of Binary TreemediumTreeDepth-First SearchBinary Treefrequency 31.3
- Count Bowl SubarraysmediumArrayStackMonotonic Stackfrequency 31.3
- Dungeon GamehardArrayDynamic ProgrammingMatrixfrequency 31.3
- Length of Longest V-Shaped Diagonal SegmenthardArrayDynamic ProgrammingMemoizationMatrixfrequency 31.3
- Longest Substring with At Least K Repeating CharactersmediumHash TableStringDivide and ConquerSliding Windowfrequency 31.3
- Make String a Subsequence Using Cyclic IncrementsmediumTwo PointersStringfrequency 31.3
- Maximum Sum Circular SubarraymediumArrayDivide and ConquerDynamic ProgrammingQueue+1frequency 31.3
- Minimum Cost to Cut a StickhardArrayDynamic ProgrammingSortingfrequency 31.3
- Nth Highest SalarymediumDatabasefrequency 31.3
- Path Sum IImediumBacktrackingTreeDepth-First SearchBinary Treefrequency 31.3
- Remove Outermost ParentheseseasyStringStackBracket Sequencesfrequency 31.3
- Reverse BitseasyDivide and ConquerBit Manipulationfrequency 31.3
- Rotate FunctionmediumArrayMathDynamic Programmingfrequency 31.3
- Substring With Largest VariancehardHash TableStringDynamic ProgrammingEnumerationfrequency 31.3
- Array PartitioneasyArrayGreedySortingCounting Sortfrequency 30.2
- Binary Search Tree IteratormediumStackTreeDesignBinary Search Tree+2frequency 30.2
- Car FleetmediumArrayStackSortingMonotonic Stackfrequency 30.2
- Custom Sort StringmediumHash TableStringSortingfrequency 30.2
- Customers Who Never OrdereasyDatabasefrequency 30.2
- Distribute Candies Among Children IImediumMathCombinatoricsEnumerationfrequency 30.2
- Find All Duplicates in an ArraymediumArrayHash TableSortingfrequency 30.2
- Find if Path Exists in GrapheasyDepth-First SearchBreadth-First SearchUnion-FindGraph Theoryfrequency 30.2
- Flatten a Multilevel Doubly Linked ListmediumLinked ListDepth-First SearchDoubly-Linked Listfrequency 30.2
- Flip String to Monotone IncreasingmediumStringDynamic Programmingfrequency 30.2
- Make Sum Divisible by PmediumArrayHash TablePrefix Sumfrequency 30.2
- Maximum Average Pass RatiomediumArrayGreedyHeap (Priority Queue)frequency 30.2
- Maximum Product of Three NumberseasyArrayMathSortingfrequency 30.2
- Merge Two Binary TreeseasyTreeDepth-First SearchBreadth-First SearchBinary Treefrequency 30.2
- Partition Array Into Two Arrays to Minimize Sum DifferencehardArrayTwo PointersBinary SearchDynamic Programming+5frequency 30.2
- Path SumeasyTreeDepth-First SearchBreadth-First SearchBinary Treefrequency 30.2
- Product Sales Analysis IeasyDatabasefrequency 30.2
- Repeated DNA SequencesmediumHash TableStringBit ManipulationSliding Window+4frequency 30.2
- Replace Elements with Greatest Element on Right SideeasyArrayfrequency 30.2
- Subarray Sums Divisible by KmediumArrayHash TablePrefix Sumfrequency 30.2
Listings only — titles, difficulty, and tags link out to LeetCode. Imported from the leetcode-company-wise-problems snapshot dated 1 June 2025. Frequency is that dataset's own relative score within a company and time range.