Uber coding interview
questions, leaked.
177 problems reported across recent Uber 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.
Uber's assessment is array-heavy. Of 177 problems in their pool, 105 are array problems. That's 59 percent of what you'll see. Most are medium difficulty, and hash tables show up constantly as a secondary tag. The good news: array problems are pattern-based and repetitive. The bad news: you'll face them under time pressure. If you blank on a sliding-window or two-pointer approach mid-OA, StealthCoder solves it in seconds, invisible to the proctor.
Top problems at Uber
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Alien Dictionary | HARD | 0.0 | 37% | Array · String · Depth-First Search |
| 02 | Bus Routes | HARD | 0.0 | 47% | Array · Hash Table · Breadth-First Search |
| 03 | Construct Quad Tree | MEDIUM | 0.0 | 77% | Array · Divide and Conquer · Tree |
| 04 | Collect Coins in a Tree | HARD | 0.0 | 36% | Array · Tree · Graph |
| 05 | Two Sum | EASY | 89.1 | 56% | Array · Hash Table |
| 06 | Squares of a Sorted Array | EASY | 0.0 | 73% | Array · Two Pointers · Sorting |
| 07 | Rotating the Box | MEDIUM | 0.0 | 79% | Array · Two Pointers · Matrix |
| 08 | Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit | MEDIUM | 0.0 | 57% | Array · Queue · Sliding Window |
| 09 | Evaluate Division | MEDIUM | 0.0 | 63% | Array · String · Depth-First Search |
| 10 | Best Time to Buy and Sell Stock | EASY | 76.3 | 55% | Array · Dynamic Programming |
| 11 | Word Search | MEDIUM | 73.2 | 45% | Array · String · Backtracking |
| 12 | Text Justification | HARD | 71.0 | 48% | Array · String · Simulation |
| 13 | Spiral Matrix | MEDIUM | 69.5 | 54% | Array · Matrix · Simulation |
| 14 | Valid Sudoku | MEDIUM | 68.7 | 62% | Array · Hash Table · Matrix |
| 15 | Group Anagrams | MEDIUM | 67.8 | 71% | Array · Hash Table · String |
| 16 | Roman to Integer | EASY | 66.9 | 65% | Hash Table · Math · String |
| 17 | Letter Combinations of a Phone Number | MEDIUM | 64.0 | 64% | Hash Table · String · Backtracking |
| 18 | Minimum Window Substring | HARD | 62.9 | 45% | Hash Table · String · Sliding Window |
| 19 | Generate Parentheses | MEDIUM | 62.9 | 77% | String · Dynamic Programming · Backtracking |
| 20 | Add Two Numbers | MEDIUM | 61.8 | 46% | Linked List · Math · Recursion |
| 21 | Merge Sorted Array | EASY | 61.8 | 53% | Array · Two Pointers · Sorting |
| 22 | Longest Common Prefix | EASY | 61.8 | 45% | String · Trie |
| 23 | Trapping Rain Water | HARD | 60.6 | 65% | Array · Two Pointers · Dynamic Programming |
| 24 | Word Break | MEDIUM | 60.6 | 48% | Array · Hash Table · String |
| 25 | Rotate Image | MEDIUM | 59.3 | 78% | Array · Math · Matrix |
| 26 | Remove Element | EASY | 59.3 | 60% | Array · Two Pointers |
| 27 | Valid Palindrome | EASY | 59.3 | 51% | Two Pointers · String |
| 28 | Search in Rotated Sorted Array | MEDIUM | 59.3 | 43% | Array · Binary Search |
| 29 | 3Sum | MEDIUM | 57.9 | 37% | Array · Two Pointers · Sorting |
| 30 | Decode Ways | MEDIUM | 57.9 | 37% | String · Dynamic Programming |
| 31 | Largest Rectangle in Histogram | HARD | 56.5 | 47% | Array · Stack · Monotonic Stack |
| 32 | Median of Two Sorted Arrays | HARD | 56.5 | 44% | Array · Binary Search · Divide and Conquer |
| 33 | Sqrt(x) | EASY | 56.5 | 40% | Math · Binary Search |
| 34 | Valid Parentheses | EASY | 56.5 | 42% | String · Stack |
| 35 | Next Permutation | MEDIUM | 56.5 | 43% | Array · Two Pointers |
| 36 | Maximum Depth of Binary Tree | EASY | 56.5 | 77% | Tree · Depth-First Search · Breadth-First Search |
| 37 | Longest Consecutive Sequence | MEDIUM | 54.9 | 47% | Array · Hash Table · Union Find |
| 38 | Merge Two Sorted Lists | EASY | 54.9 | 67% | Linked List · Recursion |
| 39 | Merge k Sorted Lists | HARD | 54.9 | 57% | Linked List · Divide and Conquer · Heap (Priority Queue) |
| 40 | Regular Expression Matching | HARD | 54.9 | 29% | String · Dynamic Programming · Recursion |
| 41 | Reverse Integer | MEDIUM | 53.3 | 30% | Math |
| 42 | Maximum Subarray | MEDIUM | 53.3 | 52% | Array · Divide and Conquer · Dynamic Programming |
| 43 | Subsets | MEDIUM | 53.3 | 81% | Array · Backtracking · Bit Manipulation |
| 44 | Word Break II | HARD | 53.3 | 54% | Array · Hash Table · String |
| 45 | Sudoku Solver | HARD | 53.3 | 64% | Array · Hash Table · Backtracking |
| 46 | Merge Intervals | MEDIUM | 51.4 | 49% | Array · Sorting |
| 47 | Longest Palindromic Substring | MEDIUM | 51.4 | 36% | Two Pointers · String · Dynamic Programming |
| 48 | Find the Index of the First Occurrence in a String | EASY | 51.4 | 45% | Two Pointers · String · String Matching |
| 49 | Remove Duplicates from Sorted Array | EASY | 51.4 | 60% | Array · Two Pointers |
| 50 | Find First and Last Position of Element in Sorted Array | MEDIUM | 51.4 | 47% | Array · Binary Search |
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 Uber 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- array105 · 59%
- string44 · 25%
- hash table36 · 20%
- dynamic programming33 · 19%
- depth first search25 · 14%
- math25 · 14%
- breadth first search22 · 12%
- matrix22 · 12%
- two pointers21 · 12%
- sorting17 · 10%
Arrays dominate the first two topics, but strings (44 problems) and hash tables (36) are real. Dynamic programming and depth-first search appear on 33 and 25 problems respectively, often layered into array or tree questions. The top problems show a mix: Two Sum and Squares of a Sorted Array are warm-ups, but Alien Dictionary and Bus Routes demand graph thinking. Start with two-pointers and sliding-window on arrays. Hash tables are non-negotiable for any follow-up. DFS and BFS are your hedge for the live OA if a problem suddenly asks you to traverse something unexpected.
Companies with similar patterns
If you prepped for Uber, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Uber.
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.
Uber interview FAQ
How many array problems should I solve before Uber's OA?+
At least 20 to 25. Arrays are 59 percent of their pool. Focus on two-pointers, sliding window, and basic manipulation. Two Sum, Squares of a Sorted Array, and Rotating the Box will train the core patterns you'll see.
Is hash table knowledge required, or can I skip it?+
Don't skip it. Hash tables appear on 36 problems and show up paired with arrays on classics like Two Sum and Group Anagrams. Plan one session specifically for hash-based counting and grouping.
What should I study first: DP or DFS?+
DFS first. It appears on 25 problems and overlaps with arrays, strings, and trees. DP (33 problems) tends to show up on harder medium and hard problems. Get DFS solid, then layer DP on top.
Are hard problems worth drilling, or should I focus on mediums?+
Focus on mediums first. They're 61 percent of the pool and include patterns like Spiral Matrix and Valid Sudoku. Hard problems like Alien Dictionary are less common but do appear. Drill them last, after mediums are solid.
How do I approach a problem I've never seen before in the OA?+
Check if it's array or string first. If you hit a wall, StealthCoder runs invisibly during the assessment and surfaces a working solution in seconds. You're not cheating. You're hedging for the gaps in what you had time to drill.