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
359 questions at Uber · all time
- Best Time to Buy and Sell Stock using StrategymediumArraySliding WindowPrefix Sumfrequency 47.5
- Calculate Digit Sum of a StringeasyStringSimulationfrequency 47.5
- Check If String Is a Prefix of ArrayeasyArrayTwo PointersStringfrequency 47.5
- Check for Contradictions in EquationshardArrayStringDepth-First SearchUnion-Find+1frequency 47.5
- Clone GraphmediumHash TableDepth-First SearchBreadth-First SearchGraph Theoryfrequency 47.5
- Construct K Palindrome StringsmediumHash TableStringGreedyCountingfrequency 47.5
- Course Schedule IVmediumDepth-First SearchBreadth-First SearchGraph TheoryTopological Sortfrequency 47.5
- Create Binary Tree From DescriptionsmediumArrayHash TableTreeBinary Treefrequency 47.5
- Employee ImportancemediumArrayHash TableTreeDepth-First Search+1frequency 47.5
- Factor CombinationsmediumBacktrackingPrime Factorizationfrequency 47.5
- Falling SquareshardArraySegment TreeOrdered Setfrequency 47.5
- Find Median from Data StreamhardTwo PointersDesignSortingHeap (Priority Queue)+1frequency 47.5
- Find Pattern in Infinite Stream ImediumArraySliding WindowRolling HashString Matching+2frequency 47.5
- Find Pattern in Infinite Stream IIhardArraySliding WindowRolling HashString Matching+2frequency 47.5
- Find the City With the Smallest Number of Neighbors at a Threshold DistancemediumDynamic ProgrammingGraph TheoryShortest PathDijkstra's Algorithm+2frequency 47.5
- Find the Distance Value Between Two ArrayseasyArrayTwo PointersBinary SearchSortingfrequency 47.5
- Fixed PointeasyArrayBinary Searchfrequency 47.5
- Flood FilleasyArrayDepth-First SearchBreadth-First SearchMatrixfrequency 47.5
- Group Shifted StringsmediumArrayHash TableStringfrequency 47.5
- Happy NumbereasyHash TableMathTwo PointersFloyd's Cycle Finding Algorithmfrequency 47.5
- Hopper Company Queries IhardDatabasefrequency 47.5
- Hopper Company Queries IIhardDatabasefrequency 47.5
- Hopper Company Queries IIIhardDatabasefrequency 47.5
- Implement Trie (Prefix Tree)mediumHash TableStringDesignTriefrequency 47.5
- Intersection of Multiple ArrayseasyArrayHash TableSortingCountingfrequency 47.5
- K Divisible Elements SubarraysmediumArrayHash TableTrieRolling Hash+2frequency 47.5
- Koko Eating BananasmediumArrayBinary Searchfrequency 47.5
- Largest Rectangle in HistogramhardArrayStackMonotonic StackRange Minimum/Maximum Queryfrequency 47.5
- Longest Palindromic SubsequencemediumStringDynamic Programmingfrequency 47.5
- Match Alphanumerical Pattern in Matrix ImediumArrayHash TableStringMatrixfrequency 47.5
- Maximize Win From Two SegmentsmediumArrayBinary SearchSliding Windowfrequency 47.5
- Maximum Depth of Binary TreeeasyTreeDepth-First SearchBreadth-First SearchBinary Treefrequency 47.5
- Maximum Increasing Triplet ValuemediumArrayOrdered Setfrequency 47.5
- Maximum Number of Eaten ApplesmediumArrayGreedyHeap (Priority Queue)frequency 47.5
- Maximum XOR for Each QuerymediumArrayBit ManipulationPrefix Sumfrequency 47.5
- Minimum Absolute Sum DifferencemediumArrayBinary SearchSortingOrdered Setfrequency 47.5
- Minimum Operations to Make Binary Array Elements Equal to One ImediumArrayBit ManipulationQueueSliding Window+1frequency 47.5
- Minimum Operations to Make Binary Array Elements Equal to One IImediumArrayDynamic ProgrammingGreedyfrequency 47.5
- Minimum Operations to Write the Letter Y on a GridmediumArrayHash TableMatrixCountingfrequency 47.5
- Minimum Score Triangulation of PolygonmediumArrayDynamic ProgrammingTriangulationPolygonsfrequency 47.5
- Minimum Sum of Squared DifferencemediumArrayBinary SearchGreedySorting+1frequency 47.5
- Nearest Exit from Entrance in MazemediumArrayBreadth-First SearchMatrixfrequency 47.5
- Number Of Ways To Reconstruct A TreehardArrayHash TableTreeGraph Theory+1frequency 47.5
- Number of Nodes in the Sub-Tree With the Same LabelmediumHash TableTreeDepth-First SearchBreadth-First Search+2frequency 47.5
- Number of People That Can Be Seen in a GridmediumArrayStackMatrixMonotonic Stackfrequency 47.5
- Number of Strings That Appear as Substrings in WordeasyArrayStringfrequency 47.5
- Number of Ways to Reach Destination in the GridhardMathDynamic ProgrammingCombinatoricsfrequency 47.5
- One Edit DistancemediumTwo PointersStringfrequency 47.5
- Optimal Account BalancinghardArrayDynamic ProgrammingBacktrackingBit Manipulation+1frequency 47.5
- Palindrome PermutationeasyHash TableStringBit Manipulationfrequency 47.5
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.