MongoDB LeetCode Questions
24 questions all-time · 3 easy · 15 medium · 6 hard
| # | Problem | Difficulty | Frequency | Acceptance |
|---|---|---|---|---|
| 1 | Word Break Array, Hash Table, String, Dynamic Programming, Trie, Memoization | Medium | 100 | 0.5% |
| 2 | Implement Trie (Prefix Tree) Hash Table, String, Design, Trie | Medium | 100 | 0.7% |
| 3 | Intersection of Two Arrays Array, Hash Table, Two Pointers, Binary Search, Sorting | Easy | 97 | 0.8% |
| 4 | Snapshot Array Array, Hash Table, Binary Search, Design | Medium | 97 | 0.4% |
| 5 | Merge k Sorted Lists Linked List, Divide and Conquer, Heap (Priority Queue), Merge Sort | Hard | 85 | 0.6% |
| 6 | Text Justification Array, String, Simulation | Hard | 85 | 0.5% |
| 7 | Convert JSON String to Object | Hard | 80 | 0.6% |
| 8 | LRU Cache Hash Table, Linked List, Design, Doubly-Linked List | Medium | 80 | 0.5% |
| 9 | Insert Interval Array | Medium | 73 | 0.5% |
| 10 | Web Crawler Multithreaded Depth-First Search, Breadth-First Search, Concurrency | Medium | 73 | 0.5% |
| 11 | Stock Price Fluctuation Hash Table, Design, Heap (Priority Queue), Data Stream, Ordered Set | Medium | 73 | 0.5% |
| 12 | Course Schedule II Depth-First Search, Breadth-First Search, Graph Theory, Topological Sort | Medium | 73 | 0.6% |
| 13 | Merge Intervals Array, Sorting | Medium | 73 | 0.5% |
| 14 | Merge Two Binary Trees Tree, Depth-First Search, Breadth-First Search, Binary Tree | Easy | 63 | 0.8% |
| 15 | Search in Rotated Sorted Array Array, Binary Search | Medium | 63 | 0.5% |
| 16 | Sliding Window Maximum Array, Queue, Sliding Window, Heap (Priority Queue), Monotonic Queue | Hard | 63 | 0.5% |
| 17 | Lowest Common Ancestor of a Binary Tree Tree, Depth-First Search, Binary Tree | Medium | 63 | 0.7% |
| 18 | Design Search Autocomplete System String, Depth-First Search, Design, Trie, Sorting, Heap (Priority Queue), Data Stream | Hard | 63 | 0.5% |
| 19 | Lowest Common Ancestor of a Binary Tree III Hash Table, Two Pointers, Tree, Binary Tree | Medium | 63 | 0.8% |
| 20 | String Compression Two Pointers, String | Medium | 63 | 0.6% |
| 21 | Word Break II Array, Hash Table, String, Dynamic Programming, Backtracking, Trie, Memoization | Hard | 63 | 0.6% |
| 22 | Merge Two Sorted Lists Linked List, Recursion | Easy | 63 | 0.7% |
| 23 | Clone Graph Hash Table, Depth-First Search, Breadth-First Search, Graph Theory | Medium | 63 | 0.7% |
| 24 | Time Based Key-Value Store Hash Table, String, Binary Search, Design | Medium | 63 | 0.5% |
How to read this list
The tabs at the top split the questions by how recently people said they were asked in interviews. "Last 30 Days" is the past month, "Last 3 Months" is the past quarter, and so on. "All Time" is every question on record for this company.
Frequency is a score from 0 to 100 for how often a question showed up in that time window. A higher number means it came up more often, so the list starts with the most common questions first. Acceptance is the share of submissions that pass on LeetCode. Click any question to open it on LeetCode.