Leetcode-Minimum Path Sum(dp)

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.

class Solution {public:    int minPathSum(vector<vector<int>>& grid) {        int m = grid.size();        int n = grid[0].size();        vector<vector<int>> res(m,vector<int>(n,grid[0][0]));        for(int i=1;i<m;i++)            res[i][0]=res[i-1][0]+grid[i][0];        for(int j=1;j<n;j++)            res[0][j]=res[0][j-1]+grid[0][j];        for(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])+grid[i][j];        return res[m-1][n-1];    }};