js-practice/src/array/01-matrix.js

35 lines
893 B
JavaScript

/**
* @param {number[][]} matrix
* @return {number[][]}
*/
export const updateMatrix = function (matrix) {
if (matrix.length === 0) return []
const m = matrix.length
const n = matrix[0].length
// 左上 -> 右下
for (let i = 0; i < m; i++) {
for (let j = 0; j < n; j++) {
if (matrix[i][j] !== 0) {
matrix[i][j] = m + n
if (i > 0) matrix[i][j] = Math.min(matrix[i - 1][j] + 1, matrix[i][j])
if (j > 0) matrix[i][j] = Math.min(matrix[i][j - 1] + 1, matrix[i][j])
}
}
}
// 右下 -> 左上
for (let i = m - 1; i >= 0; i--) {
for (let j = n - 1; j >= 0; j--) {
// distance
if (matrix[i][j] !== 0) {
if (j < n - 1) matrix[i][j] = Math.min(matrix[i][j], matrix[i][j + 1] + 1)
if (i < matrix.length - 1) matrix[i][j] = Math.min(matrix[i][j], matrix[i + 1][j] + 1)
}
}
}
return matrix
}