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
- Push DominoesmediumTwo PointersStringDynamic Programming6 companies
- Find All Possible Recipes from Given SuppliesmediumArrayHash TableStringGraph Theory+26 companies
- Distinct SubsequenceshardStringDynamic Programming6 companies
- Final Prices With a Special Discount in a ShopeasyArrayStackMonotonic Stack6 companies
- Couples Holding HandshardGreedyDepth-First SearchBreadth-First SearchUnion-Find+16 companies
- Min Cost Climbing StairseasyArrayDynamic Programming6 companies
- Defanging an IP AddresseasyString6 companies
- Remove Covered IntervalsmediumArraySorting6 companies
- Longest Palindrome by Concatenating Two Letter WordsmediumArrayHash TableStringGreedy+16 companies
- Find Smallest Letter Greater Than TargeteasyArrayBinary Search6 companies
- Continuous Subarray SummediumArrayHash TableMathPrefix Sum+16 companies
- Count Subarrays With Fixed BoundshardArrayQueueSliding WindowMonotonic Queue6 companies
- Plus OneeasyArrayMath6 companies
- Cherry PickuphardArrayDynamic ProgrammingMatrix6 companies
- Majority Element IImediumArrayHash TableSortingCounting+16 companies
- Maximum GapmediumArraySortingBucket SortRadix Sort+16 companies
- Length of Last WordeasyString6 companies
- 3Sum ClosestmediumArrayTwo PointersSorting6 companies
- Height CheckereasyArraySortingCounting SortBubble Sort6 companies
- Closest Prime Numbers in RangemediumMathNumber TheoryPrimality TestSieve Theory+16 companies
- Valid Perfect SquareeasyMathBinary Search6 companies
- Add BinaryeasyMathStringBit ManipulationSimulation6 companies
- Odd Even Linked ListmediumLinked List6 companies
- Repeated Substring PatterneasyStringString MatchingZ AlgorithmKnuth–Morris–Pratt Algorithm6 companies
- Rectangle AreamediumMathGeometry6 companies
- Cousins in Binary TreeeasyTreeDepth-First SearchBreadth-First SearchBinary Tree6 companies
- Greatest Common Divisor of StringseasyMathStringEuclidean AlgorithmGreatest Common Divisor6 companies
- Longest Substring with At Least K Repeating CharactersmediumHash TableStringDivide and ConquerSliding Window6 companies
- Immediate Food Delivery IImediumDatabase6 companies
- Binary Tree Inorder TraversaleasyStackTreeDepth-First SearchBinary Tree6 companies
- Find the Minimum Amount of Time to Brew PotionsmediumArraySimulationPrefix Sum6 companies
- Remove Duplicates from Sorted Array IImediumArrayTwo Pointers6 companies
- Binary Tree PathseasyStringBacktrackingTreeDepth-First Search+16 companies
- Water and Jug ProblemmediumMathDepth-First SearchBreadth-First SearchBézout's Lemma+36 companies
- Linked List Cycle IImediumHash TableLinked ListTwo PointersFloyd's Cycle Finding Algorithm6 companies
- Populating Next Right Pointers in Each Node IImediumLinked ListTreeDepth-First SearchBreadth-First Search+16 companies
- Second Highest SalarymediumDatabase6 companies
- Construct K Palindrome StringsmediumHash TableStringGreedyCounting6 companies
- Create Binary Tree From DescriptionsmediumArrayHash TableTreeBinary Tree6 companies
- Minimum Operations to Make Binary Array Elements Equal to One ImediumArrayBit ManipulationQueueSliding Window+16 companies
- Number of Strings That Appear as Substrings in WordeasyArrayString6 companies
- Car PoolingmediumArraySortingHeap (Priority Queue)Simulation+16 companies
- Excel Sheet Column TitleeasyMathString6 companies
- Online Stock SpanmediumStackDesignMonotonic StackData Stream6 companies
- Remove Duplicates from Sorted ListeasyLinked List6 companies
- Article Views IeasyDatabase6 companies
- Contiguous ArraymediumArrayHash TablePrefix Sum6 companies
- Find Winner on a Tic Tac Toe GameeasyArrayHash TableMatrixSimulation6 companies
- Max Sum of a Pair With Equal Sum of DigitsmediumArrayHash TableSortingHeap (Priority Queue)6 companies
- Count Vowel Substrings of a StringeasyHash TableString6 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.