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
- Shortest Matching SubstringhardTwo PointersStringBinary SearchString Matching1 company
- Two Sum BSTsmediumTwo PointersBinary SearchStackTree+31 company
- Two Sum Less Than KeasyArrayTwo PointersBinary SearchSorting1 company
- Apply Discount Every n OrdersmediumArrayHash TableDesign1 company
- Faulty SensoreasyArrayTwo Pointers1 company
- Get Highest Answer Rate QuestionmediumDatabase1 company
- Maximum Binary Tree IImediumTreeBinary Tree1 company
- Reported Posts IImediumDatabase1 company
- Adjacent Increasing Subarrays Detection IImediumArrayBinary Search1 company
- Check if DFS Strings Are PalindromeshardArrayHash TableStringTree+21 company
- Cracking the SafehardStringDepth-First SearchGraph TheoryEulerian Circuit+21 company
- Arithmetic SubarraysmediumArrayHash TableSorting1 company
- Check if There is a Path With Equal Number of 0's And 1'smediumArrayDynamic ProgrammingMatrix1 company
- Escape The GhostsmediumArrayMath1 company
- Filling Bookcase ShelvesmediumArrayDynamic Programming1 company
- Longest Palindromic Subsequence After at Most K OperationsmediumStringDynamic Programming1 company
- Longest Word in Dictionary through DeletingmediumArrayTwo PointersStringSorting1 company
- Maximum XOR With an Element From ArrayhardArrayBit ManipulationTrie1 company
- Number of Ways of Cutting a PizzahardArrayDynamic ProgrammingMemoizationMatrix+11 company
- Remove IntervalmediumArray1 company
- Check if Move is LegalmediumArrayMatrixEnumeration1 company
- Closest DivisorsmediumMathPrime Factorization1 company
- Closest RoomhardArrayBinary SearchSortingOrdered Set1 company
- Customer Order FrequencyeasyDatabase1 company
- Customers With Strictly Increasing PurchaseshardDatabase1 company
- Difference Between Ones and Zeros in Row and ColumnmediumArrayMatrixSimulation1 company
- Find Minimum Time to Finish All Jobs IImediumArrayGreedySorting1 company
- Find Number of Coins to Place in Tree NodeshardDynamic ProgrammingTreeDepth-First SearchSorting+21 company
- Find Number of Ways to Reach the K-th StairhardMathDynamic ProgrammingBit ManipulationMemoization+11 company
- Find the Index of the Large IntegermediumArrayBinary SearchInteractive1 company
- Find the K-or of an ArrayeasyArrayBit Manipulation1 company
- Find the Substring With Maximum CostmediumArrayHash TableStringDynamic Programming1 company
- Form Array by Concatenating Subarrays of Another ArraymediumArrayTwo PointersGreedyString Matching+11 company
- Handshakes That Don't CrosshardMathDynamic Programming1 company
- Insufficient Nodes in Root to Leaf PathsmediumTreeDepth-First SearchBinary Tree1 company
- Maximum Median Sum of Subsequences of Size 3mediumArrayMathGreedySorting+11 company
- Maximum Number of Achievable Transfer RequestshardArrayBacktrackingBit ManipulationEnumeration1 company
- Maximum Number of Non-Overlapping SubstringshardHash TableStringGreedySorting1 company
- Minimum Flips to Make Binary String CoherentmediumString1 company
- Minimum Number of Groups to Create a Valid AssignmentmediumArrayHash TableGreedy1 company
- Minimum Number of KeypressesmediumHash TableStringGreedySorting+11 company
- Minimum Time to Activate StringmediumArrayBinary Search1 company
- NPV QuerieseasyDatabase1 company
- Optimal DivisionmediumArrayMathDynamic Programming1 company
- Prison Cells After N DaysmediumArrayHash TableMathBit Manipulation+11 company
- Replace Elements in an ArraymediumArrayHash TableSimulation1 company
- Replace Question Marks in String to Minimize Its ValuemediumHash TableStringGreedySorting+21 company
- Sales by Day of the WeekhardDatabase1 company
- Sum of Beauty in the ArraymediumArray1 company
- Total Sum of Interaction Cost in Tree GroupshardArrayTreeDepth-First Search1 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.