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
1,223 questions at Bloomberg · all time
- 24 GamehardArrayMathBacktrackingfrequency 13.4
- Alien DictionaryhardArrayStringDepth-First SearchBreadth-First Search+3frequency 13.4
- Alternating Groups IImediumArraySliding Windowfrequency 13.4
- Avoid Flood in The CitymediumArrayHash TableBinary SearchGreedy+1frequency 13.4
- Balance a Binary Search TreemediumDivide and ConquerGreedyTreeDepth-First Search+2frequency 13.4
- Beautiful ArraymediumArrayMathDivide and Conquerfrequency 13.4
- Binary Tree Level Order Traversal IImediumTreeBreadth-First SearchBinary Treefrequency 13.4
- Binary Tree PathseasyStringBacktrackingTreeDepth-First Search+1frequency 13.4
- Bulls and CowsmediumHash TableStringCountingfrequency 13.4
- Calculate Amount Paid in TaxeseasyArraySimulationfrequency 13.4
- Champagne TowermediumDynamic Programmingfrequency 13.4
- Check if a Parentheses String Can Be ValidmediumStringStackGreedyBracket Sequencesfrequency 13.4
- Closest Equal Element QueriesmediumArrayHash TableBinary Searchfrequency 13.4
- Closest Prime Numbers in RangemediumMathNumber TheoryPrimality TestSieve Theory+1frequency 13.4
- Combination Sum IVmediumArrayDynamic Programmingfrequency 13.4
- Concatenation of Consecutive Binary NumbersmediumMathBit ManipulationSimulationfrequency 13.4
- Construct Binary Tree from Inorder and Postorder TraversalmediumArrayHash TableDivide and ConquerTree+1frequency 13.4
- Construct Binary Tree from Preorder and Postorder TraversalmediumArrayHash TableDivide and ConquerTree+1frequency 13.4
- Construct Quad TreemediumArrayDivide and ConquerTreeMatrixfrequency 13.4
- Convert Sorted List to Binary Search TreemediumLinked ListDivide and ConquerTreeBinary Search Tree+1frequency 13.4
- Count Beautiful Splits in an ArraymediumArrayDynamic Programmingfrequency 13.4
- Count Good TripletseasyArrayEnumerationfrequency 13.4
- Count Largest GroupeasyHash TableMathCountingfrequency 13.4
- Count Prefix and Suffix Pairs IeasyArrayStringTrieRolling Hash+2frequency 13.4
- Count Servers that CommunicatemediumArrayDepth-First SearchBreadth-First SearchUnion-Find+2frequency 13.4
- Count Total Number of Colored CellsmediumMathfrequency 13.4
- Count Vowel Substrings of a StringeasyHash TableStringfrequency 13.4
- Count of Substrings Containing Every Vowel and K Consonants IImediumHash TableStringSliding Windowfrequency 13.4
- Counting Words With a Given PrefixeasyArrayStringString Matchingfrequency 13.4
- Custom Sort StringmediumHash TableStringSortingfrequency 13.4
- Degree of an ArrayeasyArrayHash Tablefrequency 13.4
- Delete Characters to Make Fancy StringeasyStringfrequency 13.4
- Design HashSeteasyArrayHash TableLinked ListDesign+1frequency 13.4
- Determine if Two Strings Are ClosemediumHash TableStringSortingCountingfrequency 13.4
- Divide Array Into Arrays With Max DifferencemediumArrayGreedySortingfrequency 13.4
- Divide a String Into Groups of Size keasyStringSimulationfrequency 13.4
- Divisible and Non-divisible Sums DifferenceeasyMathfrequency 13.4
- Dungeon GamehardArrayDynamic ProgrammingMatrixfrequency 13.4
- Duplicate ZeroseasyArrayTwo Pointersfrequency 13.4
- Earliest Finish Time for Land and Water Rides IeasyArrayTwo PointersBinary SearchGreedy+1frequency 13.4
- Exclusive Time of FunctionsmediumArrayStackfrequency 13.4
- Fair Candy SwapeasyArrayHash TableBinary SearchSortingfrequency 13.4
- Final Prices With a Special Discount in a ShopeasyArrayStackMonotonic Stackfrequency 13.4
- Final Value of Variable After Performing OperationseasyArrayStringSimulationfrequency 13.4
- Find Center of Star GrapheasyGraph Theoryfrequency 13.4
- Find Common Elements Between Two ArrayseasyArrayHash Tablefrequency 13.4
- Find Duplicate SubtreesmediumHash TableTreeDepth-First SearchBinary Treefrequency 13.4
- Find K Pairs with Smallest SumsmediumArrayHeap (Priority Queue)frequency 13.4
- Find K-th Smallest Pair DistancehardArrayTwo PointersBinary SearchSortingfrequency 13.4
- Find Kth Bit in Nth Binary StringmediumStringRecursionSimulationfrequency 13.4
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.