动态规划算法leetcode.64

public int minPathSum(int[][] grid) {
        int m=grid.length;
        int n=grid[0].length;
        int[][] dp=new int[m][n];//表示到达(i,j)的最小路径和
        //初始化
        dp[0][0]=grid[0][0];
        for (int i = 1; i < m; i++) {
            dp[i][0]=dp[i-1][0]+grid[i][0];
        }
        for (int i = 1; i < n; i++) {
            dp[0][i]=dp[0][i-1]+grid[0][i];
        }
        //dp[i][j]等于dp[i][j-1]和dp[i-1][j]中的较小值+自身值
        for (int i = 1; i < m; i++) {
            for (int j = 1; j < n; j++) {
                dp[i][j]=Math.min(dp[i][j-1],dp[i-1][j])+grid[i][j];
            }
        }
        return dp[m-1][n-1];
    }