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 →
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