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
- 132 PatternmediumArrayBinary SearchStackMonotonic Stack+17 companies
- Sum of Subarray MinimumsmediumArrayDynamic ProgrammingStackMonotonic Stack7 companies
- Encode and Decode TinyURLmediumHash TableStringDesignHash Function7 companies
- Verifying an Alien DictionaryeasyArrayHash TableString7 companies
- Boundary of Binary TreemediumTreeDepth-First SearchBinary Tree7 companies
- Sort ListmediumLinked ListTwo PointersDivide and ConquerSorting+17 companies
- Maximum Average Subarray IeasyArraySliding Window7 companies
- Find the Smallest Divisor Given a ThresholdmediumArrayBinary Search7 companies
- Shortest Subarray to be Removed to Make Array SortedmediumArrayTwo PointersBinary SearchStack+17 companies
- Sum of Subarray RangesmediumArrayStackMonotonic Stack7 companies
- Find Eventual Safe StatesmediumDepth-First SearchBreadth-First SearchGraph TheoryTopological Sort+27 companies
- Perfect SquaresmediumMathDynamic ProgrammingBreadth-First SearchKnapsack Problem+17 companies
- Count the Number of Good SubarraysmediumArrayHash TableSliding Window7 companies
- Find Largest Value in Each Tree RowmediumTreeDepth-First SearchBreadth-First SearchBinary Tree7 companies
- Graph Valid TreemediumDepth-First SearchBreadth-First SearchUnion-FindGraph Theory7 companies
- Minimum Falling Path SummediumArrayDynamic ProgrammingMatrix7 companies
- Maximum Points You Can Obtain from CardsmediumArraySliding WindowPrefix Sum7 companies
- Recover Binary Search TreemediumTreeDepth-First SearchBinary Search TreeBinary Tree7 companies
- Serialize and Deserialize N-ary TreehardStringTreeDepth-First SearchBreadth-First Search7 companies
- 2 Keys KeyboardmediumMathDynamic Programming7 companies
- Tree DiametermediumTreeDepth-First SearchBreadth-First SearchGraph Theory+27 companies
- Predict the WinnermediumArrayMathDynamic ProgrammingRecursion+37 companies
- Third Maximum NumbereasyArraySorting7 companies
- Nth DigitmediumMathBinary Search7 companies
- Smallest String With SwapsmediumArrayHash TableStringDepth-First Search+37 companies
- Find Duplicate SubtreesmediumHash TableTreeDepth-First SearchBinary Tree7 companies
- Convert Sorted List to Binary Search TreemediumLinked ListDivide and ConquerTreeBinary Search Tree+17 companies
- Cache With Time Limitmedium6 companies
- Jump Game VImediumArrayDynamic ProgrammingQueueHeap (Priority Queue)+16 companies
- Max StackhardLinked ListStackDesignDoubly-Linked List+16 companies
- Minimum Genetic MutationmediumHash TableStringBreadth-First SearchBidirectional Search6 companies
- Minimum Penalty for a ShopmediumStringPrefix Sum6 companies
- Reaching PointshardMathEuclidean AlgorithmGreatest Common Divisor6 companies
- Replace Employee ID With The Unique IdentifiereasyDatabase6 companies
- Restaurant GrowthmediumDatabase6 companies
- Shortest Path to Get All KeyshardArrayBit ManipulationBreadth-First SearchMatrix6 companies
- String Compression IIImediumString6 companies
- Count Unguarded Cells in the GridmediumArrayMatrixSimulation6 companies
- Maximum 69 NumbereasyMathGreedy6 companies
- Number of Steps to Reduce a Number to ZeroeasyMathBit Manipulation6 companies
- Invalid TweetseasyDatabase6 companies
- Valid Word AbbreviationeasyTwo PointersString6 companies
- Web Crawler MultithreadedmediumDepth-First SearchBreadth-First SearchConcurrency6 companies
- Stock Price FluctuationmediumHash TableDesignHeap (Priority Queue)Data Stream+16 companies
- Binary GapeasyBit Manipulation6 companies
- Investments in 2016mediumDatabase6 companies
- Number of Black BlocksmediumArrayHash TableEnumeration6 companies
- Number of Connected Components in an Undirected GraphmediumDepth-First SearchBreadth-First SearchUnion-FindGraph Theory6 companies
- One Edit DistancemediumTwo PointersString6 companies
- Time Needed to Buy TicketseasyArrayQueueSimulation6 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.