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
25 questions at MongoDB · all time
- Implement Trie (Prefix Tree)mediumHash TableStringDesignTriefrequency 100.0
- Intersection of Two ArrayseasyArrayHash TableTwo PointersBinary Search+1frequency 97.1
- Snapshot ArraymediumArrayHash TableBinary SearchDesign+1frequency 97.1
- Word BreakmediumArrayHash TableStringDynamic Programming+3frequency 97.1
- LRU CachemediumHash TableLinked ListDesignDoubly-Linked Listfrequency 89.9
- Merge k Sorted ListshardLinked ListDivide and ConquerHeap (Priority Queue)Merge Sort+1frequency 85.3
- Text JustificationhardArrayStringSimulationfrequency 85.3
- Convert JSON String to Objecthardfrequency 79.7
- Web Crawler MultithreadedmediumDepth-First SearchBreadth-First SearchConcurrencyfrequency 79.7
- Course Schedule IImediumDepth-First SearchBreadth-First SearchGraph TheoryTopological Sortfrequency 72.6
- Insert IntervalmediumArrayfrequency 72.6
- Merge IntervalsmediumArraySortingQuicksortfrequency 72.6
- Sliding Window MaximumhardArrayQueueSliding WindowHeap (Priority Queue)+2frequency 72.6
- Stock Price FluctuationmediumHash TableDesignHeap (Priority Queue)Data Stream+1frequency 72.6
- Clone GraphmediumHash TableDepth-First SearchBreadth-First SearchGraph Theoryfrequency 62.5
- Compare Version NumbersmediumTwo PointersStringfrequency 62.5
- Design Search Autocomplete SystemhardStringDepth-First SearchDesignTrie+3frequency 62.5
- Lowest Common Ancestor of a Binary Tree IIImediumHash TableTwo PointersTreeBinary Tree+2frequency 62.5
- Merge Two Binary TreeseasyTreeDepth-First SearchBreadth-First SearchBinary Treefrequency 62.5
- Merge Two Sorted ListseasyLinked ListRecursionfrequency 62.5
- Search in Rotated Sorted ArraymediumArrayBinary Searchfrequency 62.5
- String CompressionmediumTwo PointersStringfrequency 62.5
- Time Based Key-Value StoremediumHash TableStringBinary SearchDesignfrequency 62.5
- Two SumeasyArrayHash Tablefrequency 62.5
- Word Break IIhardArrayHash TableStringDynamic Programming+3frequency 62.5
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.