Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.

Note: You can only move either down or right at any point in time.

 

public class Solution {    public int minPathSum(int[][] grid) {        if(grid == null || grid.length == 0){            return 0;        }        int m = grid.length;        int n = grid[0].length;        int[][] dp = new int[m][n];        dp[0][0] = grid[0][0];                for(int i=1;i