Robinhood Coding Interview Questions
25 Robinhood coding interview problems with full optimal solutions — 5 easy, 16 medium, 4 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Robinhood interviewer values, and a FAQ section.
Showing 4 problems of 25
- #23hardfrequently asked
23. Merge k Sorted Lists
Given an array of k sorted linked lists, merge them into one sorted list. Robinhood asks this as the canonical heap-of-streams problem — it maps directly to merging k sorted streams of trades or price-feed events.
4 free resourcesSolve → - #42hardfrequently asked
42. Trapping Rain Water
Given heights representing an elevation map, compute how much water it can trap after raining. Robinhood asks this as a hard-tier classical problem to see whether you reach for two-pointer over DP-of-max-arrays, and whether you can articulate the invariant cleanly.
3 free resourcesSolve → - #239hardfrequently asked
239. Sliding Window Maximum
Given an array and a window size k, return an array of the maximum in each sliding window of size k. Robinhood asks this because rolling-max patterns power high-watermark queries in market-data analytics and order-book monitoring.
3 free resourcesSolve → - #295hardfrequently asked
295. Find Median from Data Stream
Design a streaming structure that supports addNum and findMedian. Robinhood asks this because the two-heap pattern maps directly to real-time price-feed statistics and rolling-window analytics on trade data.
3 free resourcesSolve →
Related interview-prep guides
CodeSignal GCA for Tech Interviews in 2026: The Complete Guide
The CodeSignal General Coding Assessment is a 70-minute, four-task timed test scored on a 600 to 850 scale, used as a filter by Goldman Sachs, Capital One, Robinhood, Brex, and a growing list of tech and finance employers. This guide breaks down what it tests, how it scores, what it tracks during your session, and how a modern desktop setup pairs with it without showing up in proctored recordings.
Karat Technical Interview Guide 2026: How the Third-Party Loop Actually Works
Karat is technical-interview-as-a-service. Karat-employed engineers run the technical loop for the hiring company in Karat's own recorded video and coding environment. The dynamic is different from an in-house interview: the interviewer is a contractor, not a future teammate, the rubric is fixed, the session is recorded for asynchronous review, and the hiring team's engineers watch the playback a day later. This guide is the practical map of how that loop works in 2026 and how a modern desktop setup runs alongside it.
CodeInterview.io Live Coding Interview Guide (2026): What the Platform Tracks and How to Walk Through It Cleanly
CodeInterview.io is a browser-based collaborative live-coding platform. Think of it as a lighter-footprint alternative to CoderPad with an integrated video call, per-keystroke replay, and a drawing whiteboard. Smaller market share than CoderPad but shows up at a meaningful slice of YC startups and mid-market tech teams in 2026. This is what CodeInterview.io tracks, how its all-in-one workflow compares to CoderPad, and how a modern desktop AI setup pairs with it without showing up in the screen-share.