Amazon

Role: SDE (FTC)

College: Not Specified

Interview Date: March 27, 2025

Interview Type: Full-Time

Result: Not Specified

Difficulty: Hard

Rounds: 2 rounds

Topics Asked: Data Structures (Trees, Graphs, Arrays), Algorithms (Recursion, BFS, Greedy, Prefix Sum, Graph Traversal, Cycle Detection), Problem Solving, Logic Building, Optimization

Experience:

The candidate appeared for the Amazon SDE interview on March 27, 2025, which consisted of two intense Data Structures and Algorithms (DSA) rounds in a single day.

Interview Rounds: The interviewer tested the candidate on a mix of problem-solving, logic-building, and optimization awareness. A total of four DSA questions were asked, two in each round, evaluating different skillsets.

One of the questions mentioned was "Grid BFS – Virus Spread Simulation", where an infected cell spreads to adjacent non-infected ones per time unit, and the task was to compute the minimum time to infect all reachable people. This problem tested BFS using a queue, level-wise traversal (multi-source), grid bounds, and visited updates.

General concepts tested across these rounds included recursion depth (especially with tree problems), BFS reasoning (for simulation and infection spread), optimized array processing (using greedy or prefix sum techniques), and graph traversal and cycle detection.

Tips: The candidate advised mastering recursion with trees, practicing BFS from multiple sources, learning range-based greedy techniques, and becoming comfortable with graph fundamentals using adjacency lists.