[刷题]Minimum Path Sum

[LintCode]Minimum Path Sum

public class Solution {    /**     * @param grid: a list of lists of integers.     * @return: An integer, minimizes the sum of all numbers along its path     */    public int minPathSum(int[][] grid) {        // 2015-05-13        if (grid == null || grid.length == 0 || grid[0].length == 0) {            return 0;        }                int m = grid.length;        int n = grid[0].length;        int[][] sum = new int[m][n];                sum[0][0] = grid[0][0];        for (int i = 1; i < m; i++) {            sum[i][0] = sum[i - 1][0] + grid[i][0];        }        for (int j = 1; j < n; j++) {            sum[0][j] = sum[0][j - 1] + grid[0][j];        }        for (int i = 1; i < m; i++) {            for (int j = 1; j < n; j++) {                sum[i][j] = Math.min(sum[i - 1][j], sum[i][j - 1]) + grid[i][j];            }        }        return sum[m - 1][n - 1];    }}