Shortest Path in Binary Matrix

Medium

Graph · BFS · Matrix~20m

00:00

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Section 01

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Problem statement

Given an `n × n` binary matrix `grid`, return the length of the shortest **clear path** in the matrix. If there is no clear path, return `-1`. A clear path in a binary matrix is a path from the top-left cell `(0, 0)` to the bottom-right cell `(n - 1, n - 1)` such that all the visited cells of the path are `0`, and all the adjacent cells of the path are 8-directionally connected (i.e., they are different and they share an edge or a corner). The length of a clear path is the number of visited cells of this path.

Example

grid = [[0,1],[1,0]] → 2

Constraints

n == grid.length · n == grid[i].length · 1 ≤ n ≤ 100 · grid[i][j] is 0 or 1

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