AirBnb | SSE | Rejected
Summary
I applied for an SSE role at Airbnb and was rejected after completing an online assessment followed by two coding rounds and a system design interview.
Full Experience
I initiated my application through the Airbnb career portal and was subsequently contacted by an Airbnb recruiter after a few weeks. The initial screening involved an online assessment, which was a Hackerrank test comprising a single graph-based problem. Unfortunately, I don't recall the exact problem statement, but my solution resulted in a Time Limit Exceeded (TLE) error for one test case, although it passed the others.
Following the online assessment, I was invited for further interview rounds. These consisted of two coding rounds, each 45 minutes long, and one system design round, which lasted approximately 60 minutes.
Round 1 (45-min): This round focused on finding the minimum window in a string containing all characters from a given pattern. I initially suggested a brute force approach. With some hints from the interviewer, I managed to develop a more optimal solution, though my code still contained a few bugs.
Round 2 (45-min): The second coding round presented a problem similar to a sliding puzzle. I began with a DFS-based approach, which was suboptimal for this particular question. I then transitioned to a BFS-based approach, which proved to be a better solution. The interviewer pointed out a couple of errors in my code during this round.
Round 3 (System design, 1 hr): For the system design round, the problem involved designing a system to handle current weather data. The scenario was that I would receive weather data at periodic intervals from multiple sub-stations across a country. Each sub-station would provide weather data for its specific region in a defined format. The task was to build a system capable of fetching historical data and providing future weather predictions for a given region. The interviewer was primarily interested in a high-level design. I apologize if the question seems vague; I may have forgotten some of the finer details.
Verdict: I was ultimately rejected due to my performance in the coding rounds. The feedback indicated that they expected optimal solutions with minimal hints.
Interview Questions (3)
Minimum Window Substring
Given two strings s and t, return the minimum window substring of s such that every character in t (including duplicates) is included in the window. If no such substring exists, return the empty string "".
Sliding Puzzle
Solve a sliding puzzle problem, similar to the 2x3 grid puzzle where you need to move an empty tile to arrange numbers in order. The objective is to find the minimum number of moves to reach a target configuration.
Weather Data System Design
Design a system to collect current weather data from multiple sub-stations, store historical data, and provide future weather predictions for given regions. Focus on a high-level architecture.