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();
for(int i=1;i<m;i++)
grid[i][0]+=grid[i-1][0];
for(int i=1;i<n;i++)
grid[0][i]+=grid[0][i-1];
for(int i=1;i<m;i++)
for(int j=1;j<n;j++)
grid[i][j]+=min(grid[i-1][j],grid[i][j-1]);
return grid[m-1][n-1];
}
};