Snap coding interview
questions, leaked.
106 problems reported across recent Snap interviews. Top patterns: array, string, hash table. The list below is what most candidates actually saw, plus the honest play if you can't grind all of it.
Snap's coding interview is array and string heavy, with 60 array problems and 35 string problems across 106 total. Two thirds are medium difficulty, meaning you won't see many gimmes. You need speed on core patterns: sliding window (Minimum Window Substring), island traversal (Number of Islands, Making A Large Island), and graph traversal for scheduling problems. If you hit a wall on any of these mid-assessment, StealthCoder runs invisible to the proctor and surfaces a working solution in seconds. This is your safety net if prep doesn't cover the exact variant they throw at you.
Top problems at Snap
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | LRU Cache | MEDIUM | 100.0 | 45% | Hash Table · Linked List · Design |
| 02 | Minimum Window Substring | HARD | 95.9 | 45% | Hash Table · String · Sliding Window |
| 03 | Word Ladder | HARD | 94.4 | 43% | Hash Table · String · Breadth-First Search |
| 04 | Meeting Rooms II | MEDIUM | 94.4 | 52% | Array · Two Pointers · Greedy |
| 05 | Making A Large Island | HARD | 89.1 | 55% | Array · Depth-First Search · Breadth-First Search |
| 06 | Course Schedule II | MEDIUM | 89.1 | 53% | Depth-First Search · Breadth-First Search · Graph |
| 07 | Design Log Storage System | MEDIUM | 89.1 | 59% | Hash Table · String · Design |
| 08 | Word Break II | HARD | 89.1 | 54% | Array · Hash Table · String |
| 09 | Number of Islands | MEDIUM | 87.1 | 62% | Array · Depth-First Search · Breadth-First Search |
| 10 | Number of Distinct Islands | MEDIUM | 84.9 | 62% | Hash Table · Depth-First Search · Breadth-First Search |
| 11 | Bus Routes | HARD | 84.9 | 47% | Array · Hash Table · Breadth-First Search |
| 12 | Alien Dictionary | HARD | 84.9 | 37% | Array · String · Depth-First Search |
| 13 | One Edit Distance | MEDIUM | 84.9 | 34% | Two Pointers · String |
| 14 | Min Stack | MEDIUM | 84.9 | 56% | Stack · Design |
| 15 | Valid Sudoku | MEDIUM | 84.9 | 62% | Array · Hash Table · Matrix |
| 16 | Bricks Falling When Hit | HARD | 82.5 | 36% | Array · Union Find · Matrix |
| 17 | Power of Two | EASY | 82.5 | 48% | Math · Bit Manipulation · Recursion |
| 18 | Combination Sum IV | MEDIUM | 82.5 | 55% | Array · Dynamic Programming |
| 19 | Least Operators to Express Number | HARD | 82.5 | 48% | Math · Dynamic Programming · Memoization |
| 20 | Unique Binary Search Trees | MEDIUM | 82.5 | 62% | Math · Dynamic Programming · Tree |
| 21 | Largest Merge Of Two Strings | MEDIUM | 82.5 | 51% | Two Pointers · String · Greedy |
| 22 | Reverse Linked List | EASY | 82.5 | 79% | Linked List · Recursion |
| 23 | Binary Tree Vertical Order Traversal | MEDIUM | 82.5 | 57% | Hash Table · Tree · Depth-First Search |
| 24 | String Compression | MEDIUM | 82.5 | 58% | Two Pointers · String |
| 25 | Burst Balloons | HARD | 82.5 | 61% | Array · Dynamic Programming |
| 26 | Ternary Expression Parser | MEDIUM | 82.5 | 62% | String · Stack · Recursion |
| 27 | Closest Binary Search Tree Value | EASY | 82.5 | 50% | Binary Search · Tree · Depth-First Search |
| 28 | Word Abbreviation | HARD | 82.5 | 62% | Array · String · Greedy |
| 29 | Remove K Digits | MEDIUM | 82.5 | 35% | String · Stack · Greedy |
| 30 | Frog Jump | HARD | 82.5 | 47% | Array · Dynamic Programming |
| 31 | Reverse Words in a String | MEDIUM | 82.5 | 52% | Two Pointers · String |
| 32 | Game of Life | MEDIUM | 82.5 | 71% | Array · Matrix · Simulation |
| 33 | Sudoku Solver | HARD | 82.5 | 64% | Array · Hash Table · Backtracking |
| 34 | Combination Sum | MEDIUM | 82.5 | 75% | Array · Backtracking |
| 35 | Combination Sum II | MEDIUM | 82.5 | 58% | Array · Backtracking |
| 36 | Wildcard Matching | HARD | 82.5 | 30% | String · Dynamic Programming · Greedy |
| 37 | Basic Calculator II | MEDIUM | 76.9 | 46% | Math · String · Stack |
| 38 | Shortest Path in a Grid with Obstacles Elimination | HARD | 69.7 | 46% | Array · Breadth-First Search · Matrix |
| 39 | Cheapest Flights Within K Stops | MEDIUM | 69.7 | 40% | Dynamic Programming · Depth-First Search · Breadth-First Search |
| 40 | Word Search | MEDIUM | 69.7 | 45% | Array · String · Backtracking |
| 41 | Best Time to Buy and Sell Stock III | HARD | 65.1 | 51% | Array · Dynamic Programming |
| 42 | Decode Ways | MEDIUM | 65.1 | 37% | String · Dynamic Programming |
| 43 | Valid Arrangement of Pairs | HARD | 65.1 | 66% | Depth-First Search · Graph · Eulerian Circuit |
| 44 | Merge Intervals | MEDIUM | 59.5 | 49% | Array · Sorting |
| 45 | Amount of Time for Binary Tree to Be Infected | MEDIUM | 59.5 | 64% | Hash Table · Tree · Depth-First Search |
| 46 | Number of Islands II | HARD | 59.5 | 40% | Array · Hash Table · Union Find |
| 47 | Parallel Courses III | HARD | 59.5 | 67% | Array · Dynamic Programming · Graph |
| 48 | Design a Text Editor | HARD | 59.5 | 47% | Linked List · String · Stack |
| 49 | Minimum Number of Keypresses | MEDIUM | 59.5 | 71% | Hash Table · String · Greedy |
| 50 | Minimum Time to Complete All Tasks | HARD | 59.5 | 38% | Array · Binary Search · Stack |
Frequencies derived from public community-tagged interview reports. Click a row to view on LeetCode.
You have a week, maybe less. You can't out-grind the list above. StealthCoder runs invisibly during the actual Snap OA. The proctor cannot see it. Screen share cannot detect it. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know.
Get StealthCoder- array60 · 57%
- string35 · 33%
- hash table24 · 23%
- dynamic programming22 · 21%
- depth first search21 · 20%
- breadth first search21 · 20%
- matrix16 · 15%
- stack16 · 15%
- sorting16 · 15%
- binary search11 · 10%
The difficulty distribution is punishing. 32 hard problems and 67 medium means the median question is medium-to-hard, and easy problems are nearly nonexistent. Arrays dominate, but strings demand equal attention. Hash tables appear in 24 problems, often paired with strings or design patterns like LRU Cache and Design Log Storage System. Dynamic programming and graph traversal (DFS/BFS) each show up in 20+ problems, so topological sort (Course Schedule II, Alien Dictionary) and union find (Making A Large Island, Number of Distinct Islands) must be muscle memory. Start with array and string problems that combine hash tables, then move to graph traversal variants. StealthCoder is your hedge if you've only drilled one topological-sort approach and they ask for a different angle mid-interview.
Companies with similar patterns
If you prepped for Snap, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Snap.
Memorizing every problem above in a week is a fantasy. StealthCoder is the hedge: an AI overlay that's invisible during screen share. It reads the problem on screen and surfaces a working solution in under 2 seconds. Made by a working FAANG engineer who treats the OA the way companies treat hiring: as a game with rules you should know. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Snap interview FAQ
Should I focus on arrays or strings first for Snap?+
Arrays are the foundation. 60 array problems versus 35 string means array patterns will dominate your interview. But strings appear in 12 of Snap's top 15 hardest problems (Minimum Window Substring, Word Ladder, Alien Dictionary, Word Break II). Drill arrays for three days, then switch to string-heavy patterns like sliding window and trie for the final push.
How many hash table problems should I solve before my assessment?+
Hash tables appear in 24 of 106 problems, often mixed with other topics rather than standalone. Solve 8 to 10 hash table problems focusing on design (LRU Cache, Design Log Storage System) and string/array combos (Minimum Window Substring). You're not drilling hash tables in isolation; you're drilling their role in larger patterns.
Is dynamic programming a must for Snap, or is it a nice-to-have?+
22 problems involve DP, but most are bundled with other techniques like backtracking or memoization (Word Break II). If you're weak on DP, solve 5 to 6 core problems but don't skip graph and string work. The hard problems lean DP, so if you hit a medium DP variant on the assessment, that's where StealthCoder earns its keep.
What's the hardest topic I should drill last?+
Topological sort and union find each appear in roughly 4 problems but always on hard questions (Alien Dictionary, Course Schedule II, Making A Large Island, Number of Distinct Islands). These are low-frequency but high-impact. Drill them in your final two days, but don't burn time here if you're shaky on array/string fundamentals.
Do I need to solve all 106 problems to be ready?+
No. Focus on the top topics: 15 to 20 array problems, 10 to 12 string problems, 5 to 8 hash table designs, and 4 to 5 graph/DP variants. That's roughly 40 to 45 problems in a week. You can't out-grind Snap's list; you need pattern recognition. Quality repetition beats volume, and if you blank mid-assessment, StealthCoder covers the gap.