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];
}
};