Find shortest path using BFS
Company: MathWorks
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: Medium
Interview Round: Take-home Project
Given an m×n grid grid where grid[r][c] = 0 represents an empty cell and 1 represents a wall, a start cell (sr, sc), and a target cell (tr, tc), you may move one step at a time in four directions (up, down, left, right) into empty cells only. Return the length of the shortest path from start to target or -1 if no path exists. Describe the algorithm and its time/space complexity, and implement it in C++/Java/JavaScript.
Quick Answer: This question evaluates a candidate's proficiency with graph traversal algorithms—particularly breadth-first search—and the ability to model grid-based shortest-path problems while reasoning about time and space complexity.