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
- Longest Arithmetic Sequence After Changing At Most One ElementmediumArrayEnumeration1 company
- Maximum Number of Groups With Increasing LengthhardArrayMathBinary SearchGreedy+11 company
- Minimum Weighted Subgraph With the Required PathshardGraph TheoryHeap (Priority Queue)Shortest Path1 company
- Make String a Subsequence Using Cyclic IncrementsmediumTwo PointersString1 company
- Substring With Largest VariancehardHash TableStringDynamic ProgrammingEnumeration1 company
- Count Paths With the Given XOR ValuemediumArrayDynamic ProgrammingBit ManipulationMatrix1 company
- Maximum Number of Operations With the Same Score IImediumArrayDynamic ProgrammingMemoization1 company
- Print Words VerticallymediumArrayStringSimulation1 company
- Reduction Operations to Make the Array Elements EqualmediumArraySorting1 company
- The Knight’s TourmediumArrayBacktrackingMatrix1 company
- Design a Number Container SystemmediumHash TableDesignHeap (Priority Queue)Ordered Set1 company
- Android Unlock PatternsmediumDynamic ProgrammingBacktrackingBit ManipulationBitmask1 company
- Path In Zigzag Labelled Binary TreemediumMathTreeBinary Tree1 company
- Short Encoding of WordsmediumArrayHash TableStringTrie1 company
- Bulb Switcher IImediumMathBit ManipulationDepth-First SearchBreadth-First Search1 company
- Find the Start and End Number of Continuous RangesmediumDatabase1 company
- Maximum Subgraph Score in a TreehardArrayDynamic ProgrammingTreeDepth-First Search1 company
- Number of Times Binary String Is Prefix-AlignedmediumArray1 company
- Number of Unique Flavors After Sharing K CandiesmediumArrayHash TableSliding Window1 company
- Maximum Number of Books You Can TakehardArrayDynamic ProgrammingStackMonotonic Stack1 company
- Minimum Swaps to Avoid Forbidden ValueshardArrayHash TableGreedyCounting1 company
- Longest Non-Decreasing Subarray After Replacing at Most One ElementmediumArrayDynamic Programming1 company
- Sender With Largest Word CountmediumArrayHash TableStringCounting1 company
- Sum of Good SubsequenceshardArrayHash TableDynamic Programming1 company
- Design an Expression Tree With Evaluate FunctionmediumArrayMathStackTree+21 company
- Graph Connectivity With ThresholdhardArrayMathUnion-FindNumber Theory1 company
- All the Matches of the LeagueeasyDatabase1 company
- Average Height of Buildings in Each SegmentmediumArraySortingHeap (Priority Queue)Prefix Sum1 company
- Count Good SubarrayshardArrayStackBit ManipulationMonotonic Stack1 company
- Count Substrings That Differ by One CharactermediumHash TableStringDynamic ProgrammingEnumeration1 company
- Delete N Nodes After M Nodes of a Linked ListeasyLinked List1 company
- Delete Tree NodesmediumArrayTreeDepth-First SearchBreadth-First Search+11 company
- Equal Rational NumbershardMathString1 company
- Find All The Lonely NodeseasyTreeDepth-First SearchBreadth-First SearchBinary Tree1 company
- Find Edges in Shortest PathshardDepth-First SearchBreadth-First SearchGraph TheoryHeap (Priority Queue)+11 company
- Find Smallest Common Element in All RowsmediumArrayHash TableBinary SearchMatrix+11 company
- Find the Level of Tree with Minimum SummediumTreeDepth-First SearchBreadth-First SearchBinary Tree1 company
- Get the Second Most Recent ActivityhardDatabase1 company
- Greatest English Letter in Upper and Lower CaseeasyHash TableStringEnumeration1 company
- Make the Prefix Sum Non-negativemediumArrayGreedyHeap (Priority Queue)1 company
- Maximize Number of Nice DivisorshardMathRecursionNumber Theory1 company
- Maximum Number of Intersections on the CharthardArrayHash TableMathBinary Indexed Tree+31 company
- Maximum Number of Operations With the Same Score IeasyArraySimulation1 company
- Maximum Price to Fill a BagmediumArrayGreedySorting1 company
- Maximum Score Of Spliced ArrayhardArrayDynamic Programming1 company
- Maximum Subtree of the Same ColormediumArrayDynamic ProgrammingTreeDepth-First Search1 company
- Minimum Cost to Separate Sentence Into RowsmediumStringDynamic Programming1 company
- Minimum Deletions to Make Array BeautifulmediumArrayStackGreedy1 company
- Minimum IncompatibilityhardArrayHash TableDynamic ProgrammingBit Manipulation+11 company
- Minimum Operations to Halve Array SummediumArrayGreedyHeap (Priority Queue)1 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.