Whiteboard Confidential

Longest Consecutive Sequence: Go Interview with a FAANG Engineer


Listen Later

A candidate works through three algorithmic problems in Go during a mock interview with a senior FAANG engineer. This mock touched on correctness, complexity tradeoffs, implementation clarity, and communication — the core signals real interviewers evaluate.🧩 Problem 1 — Longest Consecutive Sequence (Unsorted Array)Design an O(n) solution using a hash set to identify sequence starts and expand. Covers duplicate handling, boundary detection, and correctness reasoning without sorting.🧩 Problem 2 — Binary Tree Level Order TraversalClassic BFS over tree nodes, using a queue and level-by-level batching. Discussion includes space complexity, queue growth, and common implementation pitfalls.🧩 Problem 3 — Cutting Trees on a Cliff (Grid Stability / Connectivity)After removing one tree, determine which remaining trees are still connected to the bottom row. Involves multi-source BFS/DFS from stable nodes, component tracking, and correctness guarantees for 4-directional connectivity.

Key skills demonstrated• Translating verbal reasoning into clean Go implementations• Maintaining communication while coding (a major FAANG evaluation axis)• Applying BFS/DFS patterns across trees and grids• Identifying optimal vs. suboptimal approaches via time/space analysis• Handling interviewer hints and recalibrating solutions• Ensuring correctness through example-driven verification👉 Book coaching or watch more mock interviews: https://www.interviewing.io📝 Interview transcript & feedback: https://interviewing.io/mocks/faang-go-longest-consecutive-sequence🔗 Explore more FAANG interviews: https://www.interviewing.io/mocksDisclaimer: All interviews are shared with explicit permission from the interviewer and interviewee. All candidates remain anonymous.

...more
View all episodesView all episodes
Download on the App Store

Whiteboard ConfidentialBy interviewing.io