Problems
Callback's own problems and the LeetCode questions companies have been asking, in one place — pick a category, then filter by company, frequency, status, difficulty, topic, and language.
Asked on LeetCode
3,115 questions · all time
- Set MismatcheasyArrayHash TableBit ManipulationSorting5 companies
- Path with Maximum GoldmediumArrayBacktrackingMatrix5 companies
- Increasing Triplet SubsequencemediumArrayGreedyLongest Increasing Subsequence5 companies
- Flatten Binary Tree to Linked ListmediumLinked ListStackTreeDepth-First Search+15 companies
- Shortest Common SupersequencehardStringDynamic ProgrammingLongest Common Subsequence5 companies
- Shuffle the ArrayeasyArray5 companies
- Single Number IImediumArrayBit Manipulation5 companies
- Critical Connections in a NetworkhardDepth-First SearchGraph TheoryBiconnected ComponentBridge (Graph)5 companies
- Can Make Arithmetic Progression From SequenceeasyArraySorting5 companies
- Largest Divisible SubsetmediumArrayMathDynamic ProgrammingSorting5 companies
- Longest Substring with At Most Two Distinct CharactersmediumHash TableStringSliding Window5 companies
- Zero Array Transformation IImediumArrayTwo PointersBinary SearchPrefix Sum5 companies
- Count Good NumbersmediumMathRecursion5 companies
- Kids With the Greatest Number of CandieseasyArray5 companies
- Maximum Number of Vowels in a Substring of Given LengthmediumStringSliding Window5 companies
- Customers Who Never OrdereasyDatabase5 companies
- Reverse String IIeasyTwo PointersString5 companies
- Design Circular DequemediumArrayLinked ListDesignQueue5 companies
- Most Profitable Path in a TreemediumArrayTreeDepth-First SearchBreadth-First Search+15 companies
- Patching ArrayhardArrayGreedy5 companies
- Shortest Distance to a CharactereasyArrayTwo PointersString5 companies
- Maximum Sum of Distinct Subarrays With Length KmediumArrayHash TableSliding Window5 companies
- Partition ListmediumLinked ListTwo Pointers5 companies
- Product Sales Analysis IIImediumDatabase5 companies
- Maximum Number of Points From Grid QuerieshardArrayTwo PointersBreadth-First SearchUnion-Find+35 companies
- Image SmoothereasyArrayMatrix5 companies
- Employee BonuseasyDatabase5 companies
- Queries Quality and PercentageeasyDatabase5 companies
- Remove Outermost ParentheseseasyStringStackBracket Sequences5 companies
- Reordered Power of 2mediumHash TableMathSortingCounting+15 companies
- All Possible Full Binary TreesmediumDynamic ProgrammingTreeRecursionMemoization+15 companies
- Create Maximum NumberhardArrayTwo PointersStackGreedy+15 companies
- Delete Duplicate Folders in SystemhardArrayHash TableStringDepth-First Search+35 companies
- Minimum Deletions to Make String BalancedmediumStringDynamic ProgrammingStack5 companies
- Countereasy5 companies
- Friend Requests II: Who Has the Most FriendsmediumDatabase5 companies
- Maximum Sum of 3 Non-Overlapping SubarrayshardArrayDynamic ProgrammingSliding WindowPrefix Sum5 companies
- Customer Who Visited but Did Not Make Any TransactionseasyDatabase5 companies
- Find Lucky Integer in an ArrayeasyArrayHash TableCounting5 companies
- Find N Unique Integers Sum up to ZeroeasyArrayMath5 companies
- Consecutive NumbersmediumDatabase5 companies
- Find if Path Exists in GrapheasyDepth-First SearchBreadth-First SearchUnion-FindGraph Theory5 companies
- How Many Numbers Are Smaller Than the Current NumbereasyArrayHash TableSortingCounting Sort5 companies
- Lemonade ChangeeasyArrayGreedy5 companies
- Product Price at a Given DatemediumDatabase5 companies
- Strange PrinterhardStringDynamic Programming5 companies
- Finding Pairs With a Certain SummediumArrayHash TableDesign5 companies
- Minimum Value to Get Positive Step by Step SumeasyArrayPrefix Sum5 companies
- Maximum XOR of Two Numbers in an ArraymediumArrayHash TableBit ManipulationTrie5 companies
- Confirmation RatemediumDatabase5 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.