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
3,110 questions · all time
- Fraction to Recurring DecimalmediumHash TableMathString7 companies
- Reverse PairshardArrayBinary SearchDivide and ConquerBinary Indexed Tree+47 companies
- Rotating the BoxmediumArrayTwo PointersMatrix7 companies
- Palindrome NumbereasyMath7 companies
- Sliding PuzzlehardArrayDynamic ProgrammingBacktrackingBreadth-First Search+57 companies
- Redundant ConnectionmediumDepth-First SearchBreadth-First SearchUnion-FindGraph Theory7 companies
- Merge In Between Linked ListsmediumLinked List7 companies
- Maximum SwapmediumMathGreedy7 companies
- Minimum Swaps to Group All 1's Together IImediumArraySliding Window7 companies
- Partition to K Equal Sum SubsetsmediumArrayDynamic ProgrammingBacktrackingBit Manipulation+27 companies
- Count Number of Nice SubarraysmediumArrayHash TableMathSliding Window+17 companies
- Greatest Sum Divisible by ThreemediumArrayDynamic ProgrammingGreedySorting7 companies
- Maximum Number of Occurrences of a SubstringmediumHash TableStringSliding Window7 companies
- Next Greater Element IIImediumMathTwo PointersString7 companies
- Best Time to Buy and Sell Stock with CooldownmediumArrayDynamic Programming7 companies
- Target SummediumArrayDynamic ProgrammingBacktrackingKnapsack Problem+17 companies
- Excel Sheet Column NumbereasyMathString7 companies
- Interleaving StringmediumStringDynamic Programming7 companies
- Shortest Unsorted Continuous SubarraymediumArrayTwo PointersStackGreedy+27 companies
- First Bad VersioneasyBinary SearchInteractive7 companies
- Merge Two Binary TreeseasyTreeDepth-First SearchBreadth-First SearchBinary Tree7 companies
- Robot Room CleanerhardBacktrackingInteractive7 companies
- Sort Characters By FrequencymediumHash TableStringSortingHeap (Priority Queue)+27 companies
- Binary Search Tree IteratormediumStackTreeDesignBinary Search Tree+27 companies
- Find the Winner of the Circular GamemediumArrayMathRecursionQueue+17 companies
- Add Two IntegerseasyMath7 companies
- Palindrome PartitioningmediumStringDynamic ProgrammingBacktracking7 companies
- Binary SearcheasyArrayBinary Search7 companies
- Delete and EarnmediumArrayHash TableDynamic Programming7 companies
- Find the Index of the First Occurrence in a StringeasyTwo PointersStringString MatchingZ Algorithm+27 companies
- Rotate ListmediumLinked ListTwo Pointers7 companies
- Peak Index in a Mountain ArraymediumArrayBinary SearchTernary Search7 companies
- Furthest Building You Can ReachmediumArrayGreedyHeap (Priority Queue)7 companies
- Maximum Width of Binary TreemediumTreeDepth-First SearchBreadth-First SearchBinary Tree7 companies
- Subarray Sums Divisible by KmediumArrayHash TablePrefix Sum7 companies
- Zigzag ConversionmediumString7 companies
- Design A LeaderboardmediumHash TableDesignSorting7 companies
- Insert into a Binary Search TreemediumTreeBinary Search TreeBinary Tree7 companies
- Valid Triangle NumbermediumArrayTwo PointersBinary SearchGreedy+17 companies
- TrianglemediumArrayDynamic Programming7 companies
- Possible BipartitionmediumDepth-First SearchBreadth-First SearchUnion-FindGraph Theory+27 companies
- Balanced Binary TreeeasyTreeDepth-First SearchBinary Tree7 companies
- Nearest Exit from Entrance in MazemediumArrayBreadth-First SearchMatrix7 companies
- Substring with Concatenation of All WordshardHash TableStringSliding Window7 companies
- Russian Doll EnvelopeshardArrayBinary SearchDynamic ProgrammingSorting+17 companies
- Unique Paths IIIhardArrayBacktrackingBit ManipulationMatrix+17 companies
- Minimum Absolute DifferenceeasyArraySorting7 companies
- Find K Pairs with Smallest SumsmediumArrayHeap (Priority Queue)7 companies
- K-th Symbol in GrammarmediumMathBit ManipulationRecursion7 companies
- Same TreeeasyTreeDepth-First SearchBreadth-First SearchBinary Tree7 companies
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.