【leetcode】Minimum Path Sum

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.

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题解：类似Unique Paths这道题，只是初始化和更新answer数组的方式不同。

代码如下(Java):

 1 public class Solution {

 2     public int minPathSum(int[][] grid) {

 3         int m = grid.length;

 4         int n = grid[0].length;

 5         int[][] answer = new int[m][n];

 6         

 7         answer[0][0] = grid[0][0];

 8         for(int i = 1;i < m;i++)

 9             answer[i][0] = answer[i-1][0] + grid[i][0];

10         for(int i = 1;i < n;i++)

11             answer[0][i] = answer[0][i-1] + grid[0][i];

12         

13         

14         for(int i = 1;i < m;i++)

15         {

16             for(int j = 1;j < n;j++){

17                 answer[i][j] = Math.min(answer[i-1][j],answer[i][j-1])+grid[i][j] ;

18             }

19         }

20         

21         return answer[m-1][n-1];

22     }

23 }