01_matrix.go

package main

funcupdateMatrix(mat [][]int) [][]int {
n:=len(mat)
m:=len(mat[0])

ifmat[0][0] !=0 {
mat[0][0] =m+n
 }

// Travel top down
forj:=1; j<m; j++ {
ifmat[0][j] !=0 {
mat[0][j] =mat[0][j-1] +1
 }
 }
fori:=1; i<n; i++ {
ifmat[i][0] !=0 {
mat[i][0] =mat[i-1][0] +1
 }
 }
fori:=1; i<n; i++ {
forj:=1; j<m; j++ {
ifmat[i][j] !=0 {
mat[i][j] =min(mat[i-1][j], mat[i][j-1]) +1
 }
 }
 }

// Travel up
forj:=m-2; j>=0; j-- {
ifmat[n-1][j] !=0 {
mat[n-1][j] =min(mat[n-1][j], mat[n-1][j+1]+1)
 }
 }
fori:=n-2; i>=0; i-- {
ifmat[i][m-1] !=0 {
mat[i][m-1] =min(mat[i][m-1], mat[i+1][m-1]+1)
 }
 }
fori:=n-2; i>=0; i-- {
forj:=m-2; j>=0; j-- {
ifmat[i][j] !=0 {
mat[i][j] =min(mat[i][j], min(mat[i+1][j], mat[i][j+1])+1)
 }
 }
 }

returnmat
}

funcmin(a, bint) int {
ifa<b {
returna
 }
returnb
}