Simulate robot moves on a grid
Company: Shopify
Role: Machine Learning Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Onsite
You are given an `m x n` grid and a robot that starts at position `(r, c)` (0-indexed). You are also given a string `commands` consisting of characters `'U'`, `'D'`, `'L'`, `'R'`, where each character requests moving the robot one cell up/down/left/right.
Rules:
- If a move would take the robot outside the grid, ignore that move (the robot stays in place).
Return the robot’s final position `(r, c)` after processing all commands.
Follow-ups (if time): return the full path; handle blocked cells where moves into obstacles are ignored.
Quick Answer: This question evaluates competency in grid-based simulation, state updates, boundary condition handling, and sequential command parsing. Commonly asked in Coding & Algorithms interviews to gauge correct implementation and edge-case reasoning, it assesses practical application more than abstract theory and can be extended to path reconstruction or obstacle-aware movement as follow-ups.
