Codenation

Role: SDE (Full-Time)

College: Not Specified

Interview Date: Not Specified (Article date: 2020-04-26)

Interview Type: Off-Campus, Full-Time

Result: Selected

Difficulty: Medium to Hard (Involved changing approach during DSA round)

Rounds: 4 rounds

Topics Asked: Resume Projects, Data Structures (Graphs, Dijkstra, BFS), Algorithms, System Design, Real-life problem solving, HR questions.

Experience:

This candidate was scouted via LinkedIn by a third-party company (CareerSocially) for a Full-Time SDE position.

Round 1: Telephonic, Resume Screening (30-35 minutes)
The round started with a self-introduction, followed by a 10-minute discussion on the resume, where the interviewer jumped across topics to verify knowledge. The candidate was then asked to pick 3 top projects, justify their choice, and then discuss one in detail, including the approach and potential improvements.

Round 2: Video Conference, Data Structures and Algorithm (Approximately 1 hour)
The question asked was: "Assume you have been given an undirected graph with no parallel edges. Each vertex represents a city and the edges are roads to travel to another city with different travel times (given). If now the source vertex 0 is infected with Coronavirus, what is the minimum time in which the entire graph will get infected?" The candidate initially suggested a dynamic programming approach involving BFS/DFS to find predecessors, with the minimum infection time being `min(xi + ti)`. After interviewer satisfaction with the logic, the candidate faced issues with the recurrence relation during coding and was allowed to change the implementation. The final solution involved running Dijkstra from the source to every node `S` to find the shortest time, then doing a BFS to find the maximum among them.

Round 3: Video Conference, System Design/Abstract Problem Solving
The specific questions for this round are not detailed in the snippet, but it's mentioned as a round between the DSA and CEO/HR round.

Round 4: Video Conference, CEO/HR Round (15-20 minutes)
The CEO explained CodeNation's structure. General questions were asked about the candidate, expectations from CodeNation, how they could contribute, and a time they used programming to solve a real-life task (e.g., automation scripts). The interview concluded with the candidate asking questions.

Result: The candidate received a call the next day confirming selection for the SDE position and an offer letter.