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Minimum Falling Path Sum

Problem statement

Given an n x n array of integers matrix, return the minimum sum of any falling path through matrix.

A falling path starts at any element in the first row and chooses the element in the next row that is either directly below or diagonally left/right. Specifically, the next element from position (row, col) will be (row + 1, col - 1), (row + 1, col), or (row + 1, col + 1).

Example 1:

Input: matrix = [[2,1,3],[6,5,4],[7,8,9]]Output: 13Explanation: There are two falling paths with a minimum sum as shown.

Example 2:

Input: matrix = [[-19,57],[-40,-5]]Output: -59Explanation: The falling path with a minimum sum is shown.

Constraints:

  • n == matrix.length == matrix[i].length
  • 1 <= n <= 100
  • -100 <= matrix[i][j] <= 100

My solution

/**
* @param {number[][]} matrix
* @return {number}
*/
var minFallingPathSum = function(matrix) {
let width = matrix.length;
let height = matrix[0].length;

for (let i = height - 2; i >= 0; i--) {
for (let j = 0; j < width; j++) {
if (j === 0) {
matrix[i][j] += Math.min(matrix[i + 1][j], matrix[i + 1][j + 1]);
} else if (j === width - 1) {
matrix[i][j] += Math.min(matrix[i + 1][j], matrix[i + 1][j - 1]);
} else {
matrix[i][j] += Math.min(matrix[i + 1][j], matrix[i + 1][j - 1], matrix[i + 1][j + 1]);
}
}
}

return Math.min(...matrix[0])
};