Snowflake coding interview
questions, leaked.
90 problems reported across recent Snowflake interviews. Top patterns: array, string, hash table. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
Snowflake's coding interview is 60 percent medium and hard problems, 90 total reported. You're walking in cold to a gauntlet of array, string, and hash-table questions stacked with sliding-window tricks, graph traversals, and dynamic-programming wrinkles. The median difficulty sits well above the typical online assessment. If you blank mid-problem on something like Trapping Rain Water or Minimum Window Substring, StealthCoder runs invisibly during screen share and surfaces a working solution in seconds. You're not memorizing 90 problems. You're drilling the patterns that matter, and you're carrying a real-time safety net into the live OA.
Top problems at Snowflake
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Design In-Memory File System | HARD | 100.0 | 48% | Hash Table · String · Design |
| 02 | Happy Number | EASY | 93.7 | 58% | Hash Table · Math · Two Pointers |
| 03 | Minimum Window Substring | HARD | 91.6 | 45% | Hash Table · String · Sliding Window |
| 04 | Course Schedule II | MEDIUM | 91.6 | 53% | Depth-First Search · Breadth-First Search · Graph |
| 05 | Find All Anagrams in a String | MEDIUM | 90.4 | 52% | Hash Table · String · Sliding Window |
| 06 | Word Search II | HARD | 90.4 | 37% | Array · String · Backtracking |
| 07 | String Transformation | HARD | 89.2 | 25% | Math · String · Dynamic Programming |
| 08 | Step-By-Step Directions From a Binary Tree Node to Another | MEDIUM | 83.4 | 56% | String · Tree · Depth-First Search |
| 09 | Calculate Amount Paid in Taxes | EASY | 83.4 | 68% | Array · Simulation |
| 10 | Maximum Number of Upgradable Servers | MEDIUM | 81.8 | 41% | Array · Math · Binary Search |
| 11 | Trapping Rain Water | HARD | 79.9 | 65% | Array · Two Pointers · Dynamic Programming |
| 12 | Painting the Walls | HARD | 79.9 | 49% | Array · Dynamic Programming |
| 13 | Maximum Profit in Job Scheduling | HARD | 79.9 | 54% | Array · Binary Search · Dynamic Programming |
| 14 | Parallel Courses III | HARD | 78.0 | 67% | Array · Dynamic Programming · Graph |
| 15 | Number of Ways to Form a Target String Given a Dictionary | HARD | 78.0 | 57% | Array · String · Dynamic Programming |
| 16 | Find the Maximum Length of a Good Subsequence I | MEDIUM | 78.0 | 32% | Array · Hash Table · Dynamic Programming |
| 17 | Minimum Array Length After Pair Removals | MEDIUM | 78.0 | 25% | Array · Hash Table · Two Pointers |
| 18 | Find the Maximum Length of a Good Subsequence II | HARD | 75.8 | 24% | Array · Hash Table · Dynamic Programming |
| 19 | Basic Calculator | HARD | 73.4 | 46% | Math · String · Stack |
| 20 | Throne Inheritance | MEDIUM | 67.7 | 65% | Hash Table · Tree · Depth-First Search |
| 21 | Count Vowel Substrings of a String | EASY | 67.7 | 71% | Hash Table · String |
| 22 | Regular Expression Matching | HARD | 67.7 | 29% | String · Dynamic Programming · Recursion |
| 23 | Boundary of Binary Tree | MEDIUM | 67.7 | 47% | Tree · Depth-First Search · Binary Tree |
| 24 | Two Sum | EASY | 64.2 | 56% | Array · Hash Table |
| 25 | Design Hit Counter | MEDIUM | 64.2 | 69% | Array · Binary Search · Design |
| 26 | Time Based Key-Value Store | MEDIUM | 64.2 | 49% | Hash Table · String · Binary Search |
| 27 | Reverse Nodes in k-Group | HARD | 64.2 | 63% | Linked List · Recursion |
| 28 | Populating Next Right Pointers in Each Node II | MEDIUM | 64.2 | 56% | Linked List · Tree · Depth-First Search |
| 29 | Max Area of Island | MEDIUM | 60.1 | 73% | Array · Depth-First Search · Breadth-First Search |
| 30 | Copy List with Random Pointer | MEDIUM | 60.1 | 61% | Hash Table · Linked List |
| 31 | Task Scheduler | MEDIUM | 60.1 | 62% | Array · Hash Table · Greedy |
| 32 | Merge Two Sorted Lists | EASY | 60.1 | 67% | Linked List · Recursion |
| 33 | Course Schedule | MEDIUM | 60.1 | 49% | Depth-First Search · Breadth-First Search · Graph |
| 34 | Design HashMap | EASY | 60.1 | 66% | Array · Hash Table · Linked List |
| 35 | Populating Next Right Pointers in Each Node | MEDIUM | 60.1 | 65% | Linked List · Tree · Depth-First Search |
| 36 | Encode and Decode Strings | MEDIUM | 60.1 | 50% | Array · String · Design |
| 37 | Merge k Sorted Lists | HARD | 55.0 | 57% | Linked List · Divide and Conquer · Heap (Priority Queue) |
| 38 | LRU Cache | MEDIUM | 55.0 | 45% | Hash Table · Linked List · Design |
| 39 | Basic Calculator II | MEDIUM | 55.0 | 46% | Math · String · Stack |
| 40 | Swap Nodes in Pairs | MEDIUM | 55.0 | 67% | Linked List · Recursion |
| 41 | Sliding Window Median | HARD | 55.0 | 39% | Array · Hash Table · Sliding Window |
| 42 | Patching Array | HARD | 55.0 | 54% | Array · Greedy |
| 43 | Graph Valid Tree | MEDIUM | 55.0 | 49% | Depth-First Search · Breadth-First Search · Union Find |
| 44 | Integer to English Words | HARD | 55.0 | 34% | Math · String · Recursion |
| 45 | Min Stack | MEDIUM | 55.0 | 56% | Stack · Design |
| 46 | Remove Sub-Folders from the Filesystem | MEDIUM | 48.6 | 76% | Array · String · Depth-First Search |
| 47 | Implement Trie (Prefix Tree) | MEDIUM | 48.6 | 68% | Hash Table · String · Design |
| 48 | Remove K Digits | MEDIUM | 48.6 | 35% | String · Stack · Greedy |
| 49 | Longest Univalue Path | MEDIUM | 48.6 | 43% | Tree · Depth-First Search · Binary Tree |
| 50 | Maximize Distance to Closest Person | MEDIUM | 48.6 | 49% | Array |
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 Snowflake 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- array47 · 52%
- string27 · 30%
- hash table24 · 27%
- depth first search20 · 22%
- dynamic programming15 · 17%
- breadth first search14 · 16%
- design14 · 16%
- binary search11 · 12%
- tree10 · 11%
- two pointers10 · 11%
Arrays dominate the reported problem set at 47 occurrences, followed by strings at 27 and hash-tables at 24. This trio forms the backbone of most questions. Depth-first search and dynamic-programming appear frequently enough (20 and 15 respectively) that you can't afford to skip them, but they're not the primary focus. The hard problems cluster around design and optimization: Design In-Memory File System, Word Search II, Trapping Rain Water, and Maximum Profit in Job Scheduling are all multi-pattern challenges that demand both breadth and depth. Start with array and string fundamentals, then layer in hash-table sliding-window problems. By the time you hit graph or DP, you'll have momentum. StealthCoder is your hedge for the design problems and the DP edge cases you haven't drilled.
Companies with similar patterns
If you prepped for Snowflake, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Snowflake.
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.
Snowflake interview FAQ
How many array and string problems should I solve before my Snowflake interview?+
Array and string problems represent 64 of the 90 reported questions. Drill at least 20 solid array problems and 12 string problems, mixing easy and medium. Focus on sliding-window patterns, two-pointer techniques, and in-place manipulation. That covers the bulk of what you'll face.
Is hash-table knowledge required for Snowflake?+
Yes. Hash-table appears in 24 reported problems and often pairs with string or sliding-window questions like Minimum Window Substring and Find All Anagrams in a String. You need to be fast with hash-map lookups and counting problems. Don't skip it.
What should I study first: graph problems or dynamic programming?+
Start with dynamic programming if you're short on time. It appears in 15 problems including hard ones like Trapping Rain Water and Maximum Profit in Job Scheduling. Graph and topological sort (14 and 20 problems combined) are secondary. Nail DP fundamentals first.
Are design problems common in Snowflake interviews?+
Yes. Design In-Memory File System is reported among the top problems asked. Design questions are harder and require systems thinking alongside coding. If you haven't tackled design problems before, solve at least 3 before your interview. It's a different skill.
Should I worry about the 25 hard problems if I'm weak on graphs?+
Don't panic. Hard problems cluster around arrays, dynamic programming, and design more than graphs. Breadth-first search and depth-first search appear in 14 and 20 problems respectively but aren't always hard. Master arrays and strings first, then add graph problems gradually.