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
- Bus RouteshardArrayHash TableBreadth-First Searchfrequency 100.0
- Alien DictionaryhardArrayStringDepth-First SearchBreadth-First Search+3frequency 95.2
- Longest Continuous Subarray With Absolute Diff Less Than or Equal to LimitmediumArrayQueueSliding WindowHeap (Priority Queue)+2frequency 94.4
- Number of IslandsmediumArrayDepth-First SearchBreadth-First SearchUnion-Find+1frequency 89.9
- Number of Islands IIhardArrayHash TableUnion-Findfrequency 89.9
- Construct Quad TreemediumArrayDivide and ConquerTreeMatrixfrequency 87.0
- Squares of a Sorted ArrayeasyArrayTwo PointersSortingfrequency 85.8
- First Unique NumbermediumArrayHash TableDesignQueue+1frequency 83.2
- Kth Smallest Element in a BSTmediumTreeDepth-First SearchBinary Search TreeBinary Treefrequency 82.3
- Find the Closest PalindromehardMathStringfrequency 80.8
- Word SearchmediumArrayStringBacktrackingDepth-First Search+1frequency 78.0
- Minimum Edge Reversals So Every Node Is ReachablehardDynamic ProgrammingDepth-First SearchBreadth-First SearchGraph Theoryfrequency 76.8
- Design Hit CountermediumArrayBinary SearchDesignQueue+1frequency 76.2
- Insert Delete GetRandom O(1)mediumArrayHash TableMathDesign+1frequency 76.2
- LRU CachemediumHash TableLinked ListDesignDoubly-Linked Listfrequency 76.2
- My Calendar ImediumArrayBinary SearchDesignSegment Tree+1frequency 73.4
- Word Search IIhardArrayStringBacktrackingTrie+1frequency 73.4
- Best Time to Buy and Sell StockeasyArrayDynamic Programmingfrequency 71.9
- Count Paths That Can Form a Palindrome in a TreehardHash TableBit ManipulationTreeDepth-First Searchfrequency 71.9
- Product of Array Except SelfmediumArrayPrefix Sumfrequency 71.1
- Evaluate DivisionmediumArrayStringDepth-First SearchBreadth-First Search+5frequency 70.2
- Text JustificationhardArrayStringSimulationfrequency 69.3
- Block Placement QuerieshardArrayBinary SearchBinary Indexed TreeSegment Tree+1frequency 68.4
- Making A Large IslandhardArrayDepth-First SearchBreadth-First SearchUnion-Find+1frequency 67.4
- Random Pick with WeightmediumArrayMathBinary SearchPrefix Sum+1frequency 67.4
- Leftmost Column with at Least a OnemediumArrayBinary SearchMatrixInteractivefrequency 66.4
- Course Schedule IImediumDepth-First SearchBreadth-First SearchGraph TheoryTopological Sortfrequency 65.4
- Find Minimum Time to Reach Last Room ImediumArrayGraph TheoryHeap (Priority Queue)Matrix+1frequency 65.4
- Spiral MatrixmediumArrayMatrixSimulationfrequency 64.3
- Valid SudokumediumArrayHash TableMatrixfrequency 64.3
- Final Prices With a Special Discount in a ShopeasyArrayStackMonotonic Stackfrequency 63.1
- The Earliest Moment When Everyone Become FriendsmediumArrayUnion-FindSortingfrequency 63.1
- Basic CalculatorhardMathStringStackRecursionfrequency 61.8
- Course SchedulemediumDepth-First SearchBreadth-First SearchGraph TheoryTopological Sort+1frequency 61.8
- Design In-Memory File SystemhardHash TableStringDesignTrie+1frequency 61.8
- Shortest BridgemediumArrayDepth-First SearchBreadth-First SearchMatrixfrequency 61.8
- Group AnagramsmediumArrayHash TableStringSortingfrequency 60.5
- Meeting Rooms IImediumArrayTwo PointersGreedySorting+2frequency 60.5
- Rotating the BoxmediumArrayTwo PointersMatrixfrequency 60.5
- Word BreakmediumArrayHash TableStringDynamic Programming+3frequency 60.5
- Cherry PickuphardArrayDynamic ProgrammingMatrixfrequency 59.1
- Letter Combinations of a Phone NumbermediumHash TableStringBacktrackingfrequency 59.1
- Top K Frequent WordsmediumArrayHash TableStringTrie+4frequency 59.1
- Divide Nodes Into the Maximum Number of GroupshardDepth-First SearchBreadth-First SearchUnion-FindGraph Theoryfrequency 57.5
- Escape the Spreading FirehardArrayBinary SearchBreadth-First SearchMatrixfrequency 57.5
- Serialize and Deserialize Binary TreehardStringTreeDepth-First SearchBreadth-First Search+2frequency 57.5
- The MazemediumArrayDepth-First SearchBreadth-First SearchMatrixfrequency 57.5
- Two SumeasyArrayHash Tablefrequency 57.5
- Minimum Operations to Reduce an Integer to 0mediumDynamic ProgrammingGreedyBit Manipulationfrequency 55.9
- Minimum Window SubstringhardHash TableStringSliding Windowfrequency 55.9
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.