LeetCode: Minimum Path Sum

题目

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

分析

动态规划题，

某一点的MinimumPathSum = min(左侧点的MinimumPathSum, 上侧点的MinimumPathSum) + 该点的数值

不过第一行和第一列的MinimumPathSum有些特殊，需要单独处理一下。

代码

class Solution{public:int minPathSum(vector<vector<int>> &grid){int m = grid.size();int n = grid[0].size();vector<vector<int>> res(grid);//First row and first col 's Minimum Path Sumfor (int i = 1; i < m; i++)res[i][0] += res[i-1][0];for (int i = 1; i < n; i++)res[0][i] += res[0][i-1];//Other points's Minimum Path Sumfor (int i = 1; i < m; i++)for (int j = 1; j < n; j++)res[i][j] += min(res[i-1][j], res[i][j-1]);return res[m-1][n-1];}};