ByteDance coding interview
questions, leaked.
64 problems reported across recent ByteDance interviews. Top patterns: array, string, dynamic programming. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
ByteDance's interview is array-heavy and unforgiving. Out of 64 problems in their question bank, 34 are array-based and 75% are medium or hard. You'll face sliding window, two-pointer traversals, and dynamic programming chains back-to-back. Strings and hash tables round out the core. If you hit a wall on a monotonic-stack problem or a DP recurrence mid-OA, StealthCoder surfaces a working solution in seconds, invisible to the proctor. That's your safety net while you keep talking.
Top problems at ByteDance
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | LRU Cache | MEDIUM | 100.0 | 45% | Hash Table · Linked List · Design |
| 02 | Smallest Subsequence of Distinct Characters | MEDIUM | 89.5 | 62% | String · Stack · Greedy |
| 03 | First Day Where You Have Been in All the Rooms | MEDIUM | 87.2 | 40% | Array · Dynamic Programming |
| 04 | Remove Duplicate Letters | MEDIUM | 87.2 | 51% | String · Stack · Greedy |
| 05 | Number of Islands | MEDIUM | 84.6 | 62% | Array · Depth-First Search · Breadth-First Search |
| 06 | Course Schedule | MEDIUM | 78.6 | 49% | Depth-First Search · Breadth-First Search · Graph |
| 07 | Combination Sum | MEDIUM | 74.9 | 75% | Array · Backtracking |
| 08 | Longest Substring Without Repeating Characters | MEDIUM | 74.9 | 37% | Hash Table · String · Sliding Window |
| 09 | Regular Expression Matching | HARD | 70.5 | 29% | String · Dynamic Programming · Recursion |
| 10 | Basic Calculator II | MEDIUM | 70.5 | 46% | Math · String · Stack |
| 11 | Kth Largest Element in an Array | MEDIUM | 70.5 | 68% | Array · Divide and Conquer · Sorting |
| 12 | Merge Intervals | MEDIUM | 65.1 | 49% | Array · Sorting |
| 13 | Shortest Distance from All Buildings | HARD | 65.1 | 44% | Array · Breadth-First Search · Matrix |
| 14 | House Robber | MEDIUM | 65.1 | 52% | Array · Dynamic Programming |
| 15 | Two Sum | EASY | 65.1 | 56% | Array · Hash Table |
| 16 | House Robber II | MEDIUM | 65.1 | 44% | Array · Dynamic Programming |
| 17 | Trapping Rain Water | HARD | 65.1 | 65% | Array · Two Pointers · Dynamic Programming |
| 18 | Longest Consecutive Sequence | MEDIUM | 65.1 | 47% | Array · Hash Table · Union Find |
| 19 | Search in Rotated Sorted Array | MEDIUM | 65.1 | 43% | Array · Binary Search |
| 20 | Subarray Sum Equals K | MEDIUM | 58.2 | 45% | Array · Hash Table · Prefix Sum |
| 21 | Add Two Numbers | MEDIUM | 58.2 | 46% | Linked List · Math · Recursion |
| 22 | Top K Frequent Elements | MEDIUM | 58.2 | 65% | Array · Hash Table · Divide and Conquer |
| 23 | Basic Calculator | HARD | 58.2 | 46% | Math · String · Stack |
| 24 | Sort List | MEDIUM | 58.2 | 62% | Linked List · Two Pointers · Divide and Conquer |
| 25 | Insert Delete GetRandom O(1) | MEDIUM | 58.2 | 55% | Array · Hash Table · Math |
| 26 | Combination Sum II | MEDIUM | 58.2 | 58% | Array · Backtracking |
| 27 | Number of Good Leaf Nodes Pairs | MEDIUM | 58.2 | 72% | Tree · Depth-First Search · Binary Tree |
| 28 | Maximal Square | MEDIUM | 58.2 | 49% | Array · Dynamic Programming · Matrix |
| 29 | Longest Common Subsequence | MEDIUM | 58.2 | 58% | String · Dynamic Programming |
| 30 | Sum Game | MEDIUM | 58.2 | 48% | Math · String · Greedy |
| 31 | Rotting Oranges | MEDIUM | 58.2 | 57% | Array · Breadth-First Search · Matrix |
| 32 | Delete Operation for Two Strings | MEDIUM | 58.2 | 64% | String · Dynamic Programming |
| 33 | Best Time to Buy and Sell Stock | EASY | 58.2 | 55% | Array · Dynamic Programming |
| 34 | Longest Repeating Character Replacement | MEDIUM | 48.5 | 57% | Hash Table · String · Sliding Window |
| 35 | Remove Zero Sum Consecutive Nodes from Linked List | MEDIUM | 48.5 | 53% | Hash Table · Linked List |
| 36 | Add to Array-Form of Integer | EASY | 48.5 | 45% | Array · Math |
| 37 | Minimum Area Rectangle | MEDIUM | 48.5 | 55% | Array · Hash Table · Math |
| 38 | Count Binary Substrings | EASY | 48.5 | 66% | Two Pointers · String |
| 39 | Unique Paths | MEDIUM | 48.5 | 66% | Math · Dynamic Programming · Combinatorics |
| 40 | Merge Sorted Array | EASY | 48.5 | 53% | Array · Two Pointers · Sorting |
| 41 | Compare Version Numbers | MEDIUM | 48.5 | 42% | Two Pointers · String |
| 42 | Search a 2D Matrix II | MEDIUM | 48.5 | 55% | Array · Binary Search · Divide and Conquer |
| 43 | Sum of Distances in Tree | HARD | 48.5 | 65% | Dynamic Programming · Tree · Depth-First Search |
| 44 | Open the Lock | MEDIUM | 48.5 | 61% | Array · Hash Table · String |
| 45 | Maximum Value at a Given Index in a Bounded Array | MEDIUM | 48.5 | 39% | Math · Binary Search · Greedy |
| 46 | Container With Most Water | MEDIUM | 48.5 | 58% | Array · Two Pointers · Greedy |
| 47 | Next Permutation | MEDIUM | 48.5 | 43% | Array · Two Pointers |
| 48 | Pow(x, n) | MEDIUM | 48.5 | 37% | Math · Recursion |
| 49 | Course Schedule II | MEDIUM | 48.5 | 53% | Depth-First Search · Breadth-First Search · Graph |
| 50 | Decode String | MEDIUM | 48.5 | 61% | String · Stack · Recursion |
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 ByteDance 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- array34 · 53%
- string16 · 25%
- dynamic programming15 · 23%
- hash table14 · 22%
- math11 · 17%
- breadth first search8 · 13%
- two pointers8 · 13%
- sorting7 · 11%
- linked list6 · 9%
- recursion6 · 9%
Array dominance is the first shock. It's not just 'arrays appear sometimes', it's more than half the reported problems. Hash tables and strings follow, both tied to sliding-window and greedy patterns you'll see repeatedly. Dynamic programming shows up in 15 problems, often layered with arrays and strings. Graph traversal (BFS, DFS, topological sort) accounts for a smaller slice but filters hard. The difficulty split is brutal: only 8 easy problems versus 48 medium and 8 hard. You can't muscle through on pattern recognition alone. Problems like LRU Cache, Smallest Subsequence of Distinct Characters, and Regular Expression Matching require design thinking and state management. If you haven't drilled monotonic stacks and greedy character-removal logic, StealthCoder is the hedge when the live assessment surprises you.
Companies with similar patterns
If you prepped for ByteDance, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass ByteDance.
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.
ByteDance interview FAQ
How many array problems should I solve before my ByteDance OA?+
At least 20 to 25. Arrays make up 53% of their question bank. Focus on sliding window, two-pointer, and DP-on-arrays patterns first. Merge Intervals, House Robber, and First Day Where You Have Been in All the Rooms are representative difficulty and style.
Is studying strings enough, or do I need hash tables too?+
You need both together. 16 string problems and 14 hash-table problems often interlock. Longest Substring Without Repeating Characters, Smallest Subsequence of Distinct Characters, and Remove Duplicate Letters all blend hash tables with greedy logic and stacks. Ignore neither.
What should I study first for a ByteDance interview?+
Array and string patterns, then dynamic programming. DP appears in 15 problems and often combines with arrays. Master Two Sum, Longest Substring Without Repeating Characters, and Merge Intervals before touching graph problems. That's 60% of your interview covered.
Are easy problems worth drilling, or should I focus on medium and hard?+
Skim easy, drill medium and hard. Only 8 of 64 problems are easy. You'll see at most one or two in your OA. Spend your time on the 48 medium problems and patterns like LRU Cache, Course Schedule, and Regular Expression Matching that won't feel straightforward.
Will graph and BFS problems show up, or are they rare?+
Graph and BFS appear in 8 problems each, lower frequency than arrays or strings. But Number of Islands, Course Schedule, and Shortest Distance from All Buildings are common interview favorites. Study them after mastering array and DP, and prioritize BFS over DFS for ByteDance's style.