Robinhood coding interview
questions, leaked.
15 problems reported across recent Robinhood interviews. Top patterns: array, hash table, string. The list below is what most reported candidates actually saw, plus the honest play if you can't grind all of it.
Robinhood's OA is array-heavy and medium-difficulty. Out of 15 problems across their interview, 13 involve arrays, often paired with hash tables, search, or simulation logic. You're looking at mostly mid-tier problems, one hard outlier (Text Justification), and a handful of easy gimmes. The median problem requires you to combine two or three concepts at once: build a hash map, then traverse it; simulate a priority queue; or search a grid. If you hit a wall on the live OA, StealthCoder runs invisibly during screen share and solves it in seconds, no proctor sight.
Top problems at Robinhood
| # | Problem | Diff | Frequency | Pass % | Patterns |
|---|---|---|---|---|---|
| 01 | Number of Orders in the Backlog | MEDIUM | 100.0 | 52% | Array · Heap (Priority Queue) · Simulation |
| 02 | Restore the Array From Adjacent Pairs | MEDIUM | 91.4 | 75% | Array · Hash Table · Depth-First Search |
| 03 | Check if There is a Valid Path in a Grid | MEDIUM | 87.6 | 49% | Array · Depth-First Search · Breadth-First Search |
| 04 | Count Good Meals | MEDIUM | 87.6 | 32% | Array · Hash Table |
| 05 | Ways to Split Array Into Three Subarrays | MEDIUM | 87.6 | 33% | Array · Two Pointers · Binary Search |
| 06 | Capital Gain/Loss | MEDIUM | 87.6 | 85% | Database |
| 07 | Count the Number of Consistent Strings | EASY | 87.6 | 88% | Array · Hash Table · String |
| 08 | Brightest Position on Street | MEDIUM | 87.6 | 61% | Array · Sorting · Prefix Sum |
| 09 | Top K Frequent Words | MEDIUM | 80.0 | 59% | Array · Hash Table · String |
| 10 | Minesweeper | MEDIUM | 62.1 | 68% | Array · Depth-First Search · Breadth-First Search |
| 11 | Best Time to Buy and Sell Stock | EASY | 62.1 | 55% | Array · Dynamic Programming |
| 12 | Text Justification | HARD | 62.1 | 48% | Array · String · Simulation |
| 13 | Top K Frequent Elements | MEDIUM | 53.5 | 65% | Array · Hash Table · Divide and Conquer |
| 14 | Defanging an IP Address | EASY | 53.5 | 90% | String |
| 15 | Employee Importance | MEDIUM | 53.5 | 68% | Array · Hash Table · 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 Robinhood OA. The proctor cannot see it. Screen share cannot detect it. Built by an engineer who got tired of watching his cohort grind for six months and still get filtered at the OA stage.
Get StealthCoder- array13 · 87%
- hash table6 · 40%
- string4 · 27%
- depth first search4 · 27%
- sorting3 · 20%
- heap priority queue3 · 20%
- counting3 · 20%
- breadth first search3 · 20%
- bucket sort2 · 13%
- matrix2 · 13%
Arrays dominate because Robinhood processes order flow and market data as sequences. Hash tables show up in 6 problems, almost always to count, deduplicate, or index for fast lookup. Graph traversal (DFS and BFS) each appear in 4 problems, typically to validate grids or rebuild trees from edge pairs. Heaps, sorting, and prefix-sum techniques each show in 2-3 problems. Your drill order: nail array manipulation, hash-table indexing, and grid traversal first. Those three topics account for the majority of weight. Simulation and string problems are present but lower frequency. The hard problem (Text Justification) is a string formatter, not a mathematical wall. Expect the easy problems to be genuine confidence points, not tricks. StealthCoder is your hedge if you blank on the exact heap or bucket-sort variant mid-OA.
Companies with similar patterns
If you prepped for Robinhood, these companies recycle ~60% of the same topics.
You've seen the list.
Now make sure you pass Robinhood.
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 who got tired of watching his cohort grind for six months and still get filtered at the OA stage. Works on HackerRank, CodeSignal, CoderPad, and Karat.
Robinhood interview FAQ
How many array problems should I solve before the OA?+
At least 10-12. Arrays are in 13 of 15 Robinhood problems. Prioritize: two-pointer range checks, prefix sums, and index-based lookups. Skip advanced segment-tree stuff. Array + hash table combos are their bread and butter.
Is learning both DFS and BFS necessary?+
Yes. Both appear 4 times each in their problem set, usually for grid or tree traversal. You don't need fancy recursion patterns. Master iterative DFS with a stack and BFS with a queue on a 2D matrix. One medium problem combines both.
Should I study heaps before the OA?+
Yes, but don't overdo it. Three problems involve heaps or priority queues. Learn insertion, deletion, and the heap property. Top K problems are common. Bucket sort appears twice as an alternative, so understand why heap beats sort on time for large K.
What's the hardest problem I'll see?+
Text Justification is HARD. It's a string formatter that requires careful indexing and padding logic. It's not algorithmic, it's implementation. Practice it once, then move on. The rest are medium, mostly solvable in 20-30 minutes each.
How should I approach the easy problems?+
Solve them fast and move on. Three easy problems (IP address, stock buy/sell, consistent strings) are warm-ups. They test basic array and hash-table ops. Don't second-guess yourself. Use them to build momentum before tackling the mediums.