Google coding interview
questions, leaked.
277 problems reported across recent Google 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.
Google gets 277 problems across all difficulty bands, with arrays dominating the list at 139 questions. You're looking at a median-heavy interview where two or three topics can cover half your expected ground. The problem set skews medium (150 problems), so expect questions that blend multiple patterns rather than pure pattern-matching. If you hit a wall on the live assessment, StealthCoder runs invisibly to surface working solutions in real time. Your actual edge is knowing which patterns matter most and drilling them hard before the interview.
Top problems at Google
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Two Sum | EASY | 100.0 | 56% | Array · Hash Table |
| 02 | Add Two Numbers | MEDIUM | 75.2 | 46% | Linked List · Math · Recursion |
| 03 | Trapping Rain Water | HARD | 73.7 | 65% | Array · Two Pointers · Dynamic Programming |
| 04 | Median of Two Sorted Arrays | HARD | 73.2 | 44% | Array · Binary Search · Divide and Conquer |
| 05 | Palindrome Number | EASY | 0.0 | 59% | Math |
| 06 | Longest Substring Without Repeating Characters | MEDIUM | 70.1 | 37% | Hash Table · String · Sliding Window |
| 07 | Longest Common Prefix | EASY | 70.0 | 45% | String · Trie |
| 08 | Valid Parentheses | EASY | 66.7 | 42% | String · Stack |
| 09 | Longest Consecutive Sequence | MEDIUM | 66.2 | 47% | Array · Hash Table · Union Find |
| 10 | Maximum Subarray | MEDIUM | 63.1 | 52% | Array · Divide and Conquer · Dynamic Programming |
| 11 | Best Time to Buy and Sell Stock | EASY | 0.0 | 55% | Array · Dynamic Programming |
| 12 | Roman to Integer | EASY | 0.0 | 65% | Hash Table · Math · String |
| 13 | Merge Intervals | MEDIUM | 0.0 | 49% | Array · Sorting |
| 14 | Rotate Image | MEDIUM | 57.8 | 78% | Array · Math · Matrix |
| 15 | Search in Rotated Sorted Array | MEDIUM | 57.7 | 43% | Array · Binary Search |
| 16 | 3Sum | MEDIUM | 0.0 | 37% | Array · Two Pointers · Sorting |
| 17 | Zigzag Conversion | MEDIUM | 0.0 | 52% | String |
| 18 | Reverse Linked List | EASY | 56.7 | 79% | Linked List · Recursion |
| 19 | 4Sum | MEDIUM | 56.4 | 38% | Array · Two Pointers · Sorting |
| 20 | Jump Game | MEDIUM | 55.8 | 39% | Array · Dynamic Programming · Greedy |
| 21 | Single Number | EASY | 55.4 | 76% | Array · Bit Manipulation |
| 22 | Pascal's Triangle | EASY | 55.4 | 77% | Array · Dynamic Programming |
| 23 | Group Anagrams | MEDIUM | 55.4 | 71% | Array · Hash Table · String |
| 24 | Find Median from Data Stream | HARD | 55.4 | 53% | Two Pointers · Design · Sorting |
| 25 | Maximal Rectangle | HARD | 54.3 | 54% | Array · Dynamic Programming · Stack |
| 26 | Find the Index of the First Occurrence in a String | EASY | 54.3 | 45% | Two Pointers · String · String Matching |
| 27 | Top K Frequent Words | MEDIUM | 0.0 | 59% | Array · Hash Table · String |
| 28 | Container With Most Water | MEDIUM | 0.0 | 58% | Array · Two Pointers · Greedy |
| 29 | Remove Duplicates from Sorted Array | EASY | 0.0 | 60% | Array · Two Pointers |
| 30 | Next Permutation | MEDIUM | 0.0 | 43% | Array · Two Pointers |
| 31 | Sliding Window Maximum | HARD | 0.0 | 48% | Array · Queue · Sliding Window |
| 32 | Valid Anagram | EASY | 51.4 | 67% | Hash Table · String · Sorting |
| 33 | First Missing Positive | HARD | 51.2 | 41% | Array · Hash Table |
| 34 | Jump Game II | MEDIUM | 50.9 | 42% | Array · Dynamic Programming · Greedy |
| 35 | Add Binary | EASY | 50.4 | 56% | Math · String · Bit Manipulation |
| 36 | Diameter of Binary Tree | EASY | 0.0 | 64% | Tree · Depth-First Search · Binary Tree |
| 37 | Number of Visible People in a Queue | HARD | 0.0 | 71% | Array · Stack · Monotonic Stack |
| 38 | Find Peak Element | MEDIUM | 0.0 | 47% | Array · Binary Search |
| 39 | Longest Palindromic Substring | MEDIUM | 0.0 | 36% | Two Pointers · String · Dynamic Programming |
| 40 | Russian Doll Envelopes | HARD | 0.0 | 37% | Array · Binary Search · Dynamic Programming |
| 41 | Set Matrix Zeroes | MEDIUM | 0.0 | 61% | Array · Hash Table · Matrix |
| 42 | Move Zeroes | EASY | 0.0 | 63% | Array · Two Pointers |
| 43 | Word Break | MEDIUM | 0.0 | 48% | Array · Hash Table · String |
| 44 | Number of Islands | MEDIUM | 0.0 | 62% | Array · Depth-First Search · Breadth-First Search |
| 45 | Text Justification | HARD | 48.6 | 48% | Array · String · Simulation |
| 46 | Insert Interval | MEDIUM | 47.3 | 43% | Array |
| 47 | Maximum Product Subarray | MEDIUM | 45.5 | 35% | Array · Dynamic Programming |
| 48 | Best Time to Buy and Sell Stock II | MEDIUM | 0.0 | 70% | Array · Dynamic Programming · Greedy |
| 49 | Minimum Window Substring | HARD | 0.0 | 45% | Hash Table · String · Sliding Window |
| 50 | Range Module | HARD | 0.0 | 44% | Design · Segment Tree · Ordered Set |
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 Google OA. The proctor cannot see it. Screen share cannot detect it. Built by an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share.
Get StealthCoder- array139 · 50%
- string63 · 23%
- hash table55 · 20%
- dynamic programming45 · 16%
- math39 · 14%
- two pointers35 · 13%
- binary search29 · 10%
- depth first search29 · 10%
- breadth first search29 · 10%
- sorting28 · 10%
Arrays and hash tables form the spine of Google's assessment. Together they cover over 70 problems. Strings show up in 63 problems, often layered with sliding window or hash-table logic. Dynamic programming appears in 45 questions but clusters into hard problems, so don't panic if DP feels slow right now. Two pointers, binary search, and graph traversal (DFS/BFS) each sit in the 25-35 range, making them reliable secondary patterns. The hard tier (53 problems) leans into Trapping Rain Water and Median of Two Sorted Arrays territory, multi-step problems that combine arrays, binary search, or dynamic programming. Start with array and string fundamentals, then layer in hash tables and two pointers for speed. If you blank mid-OA on a sliding window or binary search setup, StealthCoder is your backstop.
Companies with similar patterns
If you prepped for Google, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Google.
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. Built by an engineer at a top-10 tech company who can solve these problems cold but didn't want to trust himself in a 90-minute screen share. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Google interview FAQ
How many array problems should I solve before my Google interview?+
Array problems make up 50% of Google's assessment list at 139 questions. Drill at least 20-30 from easy to medium difficulty, focusing on subarrays, two pointers, and rotation. You can't memorize your way through 139, but you can own the patterns in the top problems: Two Sum, Maximum Subarray, Best Time to Buy and Sell Stock, Merge Intervals.
Is dynamic programming required for Google's interview?+
DP appears in 45 problems but mostly at hard difficulty. You don't need it day one. Master arrays, hash tables, and strings first. Once you're solid on those, DP problems become clearer because they're usually array or string problems with state. Trapping Rain Water and Maximum Subarray are the most-asked DP hybrids.
Should I study hash tables or two pointers first?+
Hash tables first. They unlock 55 problems and pair directly with arrays and strings on easy and medium questions. Two Sum, Longest Substring Without Repeating Characters, Longest Consecutive Sequence all lean on hash tables for speed. Two pointers (35 problems) is your second move, especially for sorted arrays and collision problems.
What should I do if I see a hard problem with binary search in my assessment?+
Binary search appears in only 29 problems overall, mostly medium. Hard binary search problems like Median of Two Sorted Arrays are brutal if you haven't seen the pattern. Drill the top binary search problems once arrays and sorting are solid. If you get stuck on one mid-interview, the assessment is designed to test your entire range, not just nail every hard problem.
How much time should I spend on graph problems (DFS/BFS)?+
DFS and BFS each show up in 29 problems, roughly 10% of the total. They're not the priority. Get proficient on arrays, strings, and hash tables first, then add graphs as your third tier. When you do study graphs, focus on traversal basics and how they pair with hash tables for visited tracking.