01 Matrix
Given an m x n binary matrix mat, return the distance of the nearest 0 for each cell.
The distance between two cells sharing a common edge is 1.
Note: This question is the same as 1765: https://leetcode.com/problems/map-of-highest-peak/
Example 1
0 0 0 0 1 0 0 0 0
Input
mat = [[0,0,0],[0,1,0],[0,0,0]]Output
[[0,0,0],[0,1,0],[0,0,0]]Every
1 cell is adjacent to a 0, so its nearest distance is 1 and all 0 cells have distance 0.Example 2
0 0 0 0 1 0 1 1 1
Input
mat = [[0,0,0],[0,1,0],[1,1,1]]Output
[[0,0,0],[0,1,0],[1,2,1]]The bottom-middle cell is two edges away from the nearest
0, while the other 1 cells are one edge away.Constraints
- m == mat.length
- n == mat[i].length
- 1 <= m, n <= 10^4
- 1 <= m * n <= 10^4
- mat[i][j] is either 0 or 1.
- There is at least one 0 in mat.