64. Minimum Path Sum

https://leetcode.com/problems/minimum-path-sum/description/

解题思路：

1. dp[i][j] = Math.min(dp[i-1][j], dp[i][j - 1]) + grid[i][j]; where dp[i][j] represents the minimum sum value from start point to i,j point.

代码如下：
class Solution {
public int minPathSum(int[][] grid) {

    if(grid == null) return 0;
    int row = grid.length;
    int col = grid[0].length;
    int[][] dp = new int[row][col];
    dp[0][0] = grid[0][0];
    for(int i = 1; i < row; i++) 
        dp[i][0] = dp[i-1][0] + grid[i][0];
    for(int j = 1; j < col; j++)
        dp[0][j] = dp[0][j-1] + grid[0][j];
    for(int i = 1; i < row; i++){
        for(int j = 1; j < col; j++){
            dp[i][j] = Math.min(dp[i-1][j], dp[i][j-1]) + grid[i][j];
        }
    }
    return dp[row-1][col-1];
}

}