Minimum Path Sum

题目：

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.

 1 public class Solution {
 2     public int minPathSum(int[][] grid) 
 3     {
 4         int m = grid.length;
 5         int n = grid[0].length;
 6         int[][] sum = new int [m][n];
 7         
 8         sum[0][0]=grid[0][0];
 9         for(int i=1;i<m;i++)
10         {
11             sum[i][0]=sum[i-1][0]+grid[i][0];
12         }
13         
14         for(int j=1;j<n;j++)
15         {
16             sum[0][j]=sum[0][j-1]+grid[0][j];
17         }
18         
19         for(int i=1;i<m;i++)
20            for(int j =1;j<n;j++)
21            {
22                sum[i][j]=Math.min(sum[i-1][j],sum[i][j-1])+grid[i][j];
23            }
24            
25            
26            return sum[m-1][n-1];
27     
28     }
29 }

reference： http://www.jiuzhang.com/solutions/minimum-path-sum/

posted @ 2015-09-24 05:14  Hygeia  阅读(152)  评论(0)  编辑  收藏  举报