LinkedIn coding interview
questions, leaked.
141 problems reported across recent LinkedIn interviews. Top patterns: array, hash table, string. The list below is what most candidates actually saw, plus the honest play if you can't grind all of it.
LinkedIn's coding interview hammers arrays, hash tables, and strings across 141 reported problems. You're looking at 64 percent medium difficulty, which means the bar is grinding consistency, not flashy hard problems. Most candidates spend time on random platforms and miss the actual pattern distribution. You need to know what LinkedIn actually tests. If you blank on a sliding-window or DFS problem mid-assessment, StealthCoder runs invisibly during screen share and surfaces a working solution in seconds. That's your hedge.
Top problems at LinkedIn
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Max Stack | HARD | 100.0 | 46% | Linked List · Stack · Design |
| 02 | Nested List Weight Sum II | MEDIUM | 94.7 | 66% | Stack · Depth-First Search · Breadth-First Search |
| 03 | All O`one Data Structure | HARD | 94.4 | 44% | Hash Table · Linked List · Design |
| 04 | Word Ladder | HARD | 79.1 | 43% | Hash Table · String · Breadth-First Search |
| 05 | Find the Celebrity | MEDIUM | 79.1 | 48% | Two Pointers · Graph · Interactive |
| 06 | Nested List Weight Sum | MEDIUM | 77.8 | 86% | Depth-First Search · Breadth-First Search |
| 07 | Find Leaves of Binary Tree | MEDIUM | 77.4 | 81% | Tree · Depth-First Search · Binary Tree |
| 08 | Shortest Word Distance II | MEDIUM | 77.4 | 62% | Array · Hash Table · Two Pointers |
| 09 | Maximum Subarray | MEDIUM | 77.4 | 52% | Array · Divide and Conquer · Dynamic Programming |
| 10 | Max Consecutive Ones III | MEDIUM | 0.0 | 66% | Array · Binary Search · Sliding Window |
| 11 | Valid Parentheses | EASY | 76.5 | 42% | String · Stack |
| 12 | Number of Islands | MEDIUM | 75.6 | 62% | Array · Depth-First Search · Breadth-First Search |
| 13 | Maximum Product Subarray | MEDIUM | 73.0 | 35% | Array · Dynamic Programming |
| 14 | Can Place Flowers | EASY | 72.4 | 29% | Array · Greedy |
| 15 | Search in Rotated Sorted Array | MEDIUM | 71.3 | 43% | Array · Binary Search |
| 16 | Pow(x, n) | MEDIUM | 70.6 | 37% | Math · Recursion |
| 17 | Insert Delete GetRandom O(1) | MEDIUM | 69.3 | 55% | Array · Hash Table · Math |
| 18 | Binary Tree Upside Down | MEDIUM | 69.3 | 65% | Tree · Depth-First Search · Binary Tree |
| 19 | Partition to K Equal Sum Subsets | MEDIUM | 68.7 | 38% | Array · Dynamic Programming · Backtracking |
| 20 | Find First and Last Position of Element in Sorted Array | MEDIUM | 67.9 | 47% | Array · Binary Search |
| 21 | Paint House | MEDIUM | 67.9 | 64% | Array · Dynamic Programming |
| 22 | Serialize and Deserialize Binary Tree | HARD | 66.4 | 59% | String · Tree · Depth-First Search |
| 23 | Minimum Window Substring | HARD | 64.8 | 45% | Hash Table · String · Sliding Window |
| 24 | Exclusive Time of Functions | MEDIUM | 63.9 | 65% | Array · Stack |
| 25 | Factor Combinations | MEDIUM | 63.9 | 50% | Backtracking |
| 26 | Shortest Word Distance | EASY | 63.9 | 66% | Array · String |
| 27 | Maximum Depth of Binary Tree | EASY | 63.9 | 77% | Tree · Depth-First Search · Breadth-First Search |
| 28 | Letter Combinations of a Phone Number | MEDIUM | 63.0 | 64% | Hash Table · String · Backtracking |
| 29 | Kth Largest Element in an Array | MEDIUM | 63.0 | 68% | Array · Divide and Conquer · Sorting |
| 30 | Lowest Common Ancestor of a Binary Tree | MEDIUM | 63.0 | 67% | Tree · Depth-First Search · Binary Tree |
| 31 | Lowest Common Ancestor of a Binary Search Tree | MEDIUM | 62.1 | 68% | Tree · Depth-First Search · Binary Search Tree |
| 32 | Isomorphic Strings | EASY | 62.1 | 47% | Hash Table · String |
| 33 | Process Tasks Using Servers | MEDIUM | 0.0 | 41% | Array · Heap (Priority Queue) |
| 34 | Sort Transformed Array | MEDIUM | 61.0 | 57% | Array · Math · Two Pointers |
| 35 | Symmetric Tree | EASY | 61.0 | 59% | Tree · Depth-First Search · Breadth-First Search |
| 36 | Merge Intervals | MEDIUM | 61.0 | 49% | Array · Sorting |
| 37 | Kth Smallest Product of Two Sorted Arrays | HARD | 60.0 | 31% | Array · Binary Search |
| 38 | Count Integers in Intervals | HARD | 60.0 | 34% | Design · Segment Tree · Ordered Set |
| 39 | Valid Number | HARD | 60.0 | 22% | String |
| 40 | Valid Perfect Square | EASY | 60.0 | 44% | Math · Binary Search |
| 41 | Closest Binary Search Tree Value II | HARD | 58.8 | 60% | Two Pointers · Stack · Tree |
| 42 | Second Minimum Node In a Binary Tree | EASY | 58.8 | 45% | Tree · Depth-First Search · Binary Tree |
| 43 | Max Points on a Line | HARD | 58.8 | 29% | Array · Hash Table · Math |
| 44 | Repeated DNA Sequences | MEDIUM | 57.6 | 51% | Hash Table · String · Bit Manipulation |
| 45 | Evaluate Reverse Polish Notation | MEDIUM | 57.6 | 55% | Array · Math · Stack |
| 46 | House Robber | MEDIUM | 57.6 | 52% | Array · Dynamic Programming |
| 47 | Longest Palindromic Subsequence | MEDIUM | 56.3 | 64% | String · Dynamic Programming |
| 48 | Can I Win | MEDIUM | 56.3 | 30% | Math · Dynamic Programming · Bit Manipulation |
| 49 | LRU Cache | MEDIUM | 56.3 | 45% | Hash Table · Linked List · Design |
| 50 | Binary Tree Level Order Traversal | MEDIUM | 56.3 | 71% | Tree · Breadth-First Search · Binary Tree |
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 LinkedIn OA. The proctor cannot see it. Screen share cannot detect it. Made by an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too.
Get StealthCoder- array68 · 48%
- hash table31 · 22%
- string29 · 21%
- depth first search25 · 18%
- breadth first search21 · 15%
- tree21 · 15%
- dynamic programming21 · 15%
- two pointers20 · 14%
- binary tree20 · 14%
- math20 · 14%
Array dominance is non-negotiable: 68 problems out of 141 means nearly half the assessment space. Hash tables, strings, and graph traversal (DFS and BFS combined) make up another significant chunk. What matters is that the top problems aren't pure data-structure exercises. Max Stack, All O'one Data Structure, and Word Ladder all require design thinking on top of the basic patterns. You'll see medium-difficulty array problems like Maximum Subarray and Max Consecutive Ones III that test dynamic programming and sliding-window concepts. The 26 hard problems are roughly 18 percent of the pool, so don't waste your week on hard-only grinding. Drill arrays and hash tables first, then lock in DFS, BFS, and two-pointer work. If you hit a design problem or complex multi-step DFS during the live assessment, StealthCoder is the safety net when you're running short on time.
Companies with similar patterns
If you prepped for LinkedIn, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass LinkedIn.
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 an Amazon engineer who watched the leaked-problem repo become an industry secret. He decided you should have it too. Works on HackerRank, CodeSignal, CoderPad, and Karat.
LinkedIn interview FAQ
How much should I focus on array problems for LinkedIn?+
Nearly half the problem set is array-focused. Start there. But don't solve them in isolation. Look for subproblems like sliding window (Max Consecutive Ones III), dynamic programming (Maximum Subarray), and two-pointer techniques. Arrays appear in 68 of 141 problems, so mastery here pays immediately.
Are design problems common in LinkedIn assessments?+
Design appears in 18 problems. Most show up as hard (Max Stack, All O'one Data Structure). These mix data structures with algorithmic thinking. If design isn't your strong suit, understand the patterns: custom stacks, ordered maps, frequency tracking. Don't skip them.
Should I spend time on hard problems before the assessment?+
Hard problems are 18 percent of the pool. Get your medium work tight first: 90 problems live there. Once you're solid on arrays, hash tables, DFS, and BFS at medium level, then pick hard problems that combine multiple patterns, like Word Ladder or Max Stack.
What topics should I drill in order?+
Array (68), hash table (31), string (29), and graph traversal (DFS 25, BFS 21) cover 70 percent of problems. Nail these sequentially. Two-pointer (20) and binary search (16) are supporting skills. DP and design appear in harder variants of array and string problems.
Is one week enough to prepare for LinkedIn?+
One week is tight but doable if you focus. Solve 2 to 3 medium array problems daily, then hash-table and string problems on day 4 to 5. Day 6 to 7, hit one hard problem and review patterns you fumbled. The assessment is 64 percent medium, so that's where your prep ROI is highest.