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
- Paths in Maze That Lead to Same RoommediumGraph Theory1 company
- Power Update After K-th Largest Insertion ImediumArrayHash TableMathSegment Tree+21 company
- Random Flip MatrixmediumHash TableMathReservoir SamplingRandomized1 company
- Recover the Original ArrayhardArrayHash TableTwo PointersSorting+11 company
- Remove All Ones With Row and Column FlipsmediumArrayMathBit ManipulationMatrix1 company
- Remove All Ones With Row and Column Flips IImediumArrayBit ManipulationBreadth-First SearchMatrix1 company
- Replace All Digits with CharacterseasyString1 company
- Rings and RodseasyHash TableString1 company
- Shortest Distance to Target ColormediumArrayBinary SearchDynamic Programming1 company
- Similar RGB ColoreasyMathStringEnumeration1 company
- Sort Array by Moving Items to Empty SpacehardArrayHash TableSorting1 company
- String Transforms Into Another StringhardHash TableStringGraph Theory1 company
- The Most Similar Path in a GraphhardArrayStringDynamic ProgrammingGraph Theory1 company
- The k Strongest Values in an ArraymediumArrayTwo PointersSorting1 company
- Tree of CoprimeshardArrayMathTreeDepth-First Search+11 company
- Unique Word AbbreviationmediumArrayHash TableStringDesign1 company
- Valid Word SquareeasyArrayMatrix1 company
- Watering Plants IImediumArrayTwo PointersSimulation1 company
- Word SquareshardArrayStringBacktrackingTrie1 company
- Maximum Balanced ShipmentsmediumArrayDynamic ProgrammingStackGreedy+11 company
- Count the Number of Square-Free SubsetsmediumArrayMathDynamic ProgrammingBit Manipulation+21 company
- Find the Minimum Cost Array PermutationhardArrayDynamic ProgrammingBit ManipulationBitmask1 company
- Walking Robot Simulation IImediumDesignSimulation1 company
- Find Books with No Available CopieseasyDatabase1 company
- Remove K-Balanced SubstringsmediumStringStackSimulation1 company
- The Most Frequently Ordered Products for Each CustomermediumDatabase1 company
- Get the Size of a DataFrameeasy1 company
- Maximum Sum of Subsequence With Non-adjacent ElementshardArrayDivide and ConquerDynamic ProgrammingSegment Tree1 company
- Reverse Odd Levels of Binary TreemediumTreeDepth-First SearchBreadth-First SearchBinary Tree1 company
- Maximum Product of Subsequences With an Alternating Sum Equal to KhardArrayHash TableDynamic Programming1 company
- Crawler Log FoldereasyArrayStringStack1 company
- Unpopular BooksmediumDatabase1 company
- Allow One Function Calleasy1 company
- Available Captures for RookeasyArrayMatrixSimulation1 company
- Find Players With Zero or One LossesmediumArrayHash TableSortingCounting1 company
- Find the Occurrence of First Almost Equal SubstringhardStringString MatchingKnuth–Morris–Pratt Algorithm1 company
- Maximize the Number of Target Nodes After Connecting Trees ImediumTreeDepth-First SearchBreadth-First Search1 company
- Minimum Cost Tree From Leaf ValuesmediumArrayDynamic ProgrammingStackGreedy+21 company
- Minimum Moves to Move a Box to Their Target LocationhardArrayBreadth-First SearchHeap (Priority Queue)Matrix1 company
- Reconstruct Original Digits from EnglishmediumHash TableMathString1 company
- Minimum Number of Operations to Make Array XOR Equal to KmediumArrayBit Manipulation1 company
- Minimum Subsequence in Non-Increasing OrdereasyArrayGreedySorting1 company
- Pancake SortingmediumArrayTwo PointersGreedySorting1 company
- Rearrange Array to Maximize Prefix ScoremediumArrayGreedySortingPrefix Sum1 company
- XOR After Range Multiplication Queries ImediumArrayDivide and ConquerSimulationPrefix Sum1 company
- Analyze Subscription ConversionmediumDatabase1 company
- Check Digitorial PermutationmediumMathCounting1 company
- Choose K Elements With Maximum SummediumArraySortingHeap (Priority Queue)1 company
- Find Maximum Number of Non Intersecting SubstringsmediumHash TableStringDynamic ProgrammingGreedy1 company
- Find the Sequence of Strings Appeared on the ScreenmediumStringSimulation1 company
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.