Leetcode-Unique Paths(dp)

A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).

The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish' in the diagram below).

How many possible unique paths are there?



Above is a 3 x 7 grid. How many possible unique paths are there?

Note: m and n will be at most 100.

class Solution {
public:
int uniquePaths(int m, int n) {
vector<vector<int>> res(m,vector<int>(n,1));
for(int i=1;i<m;i++)
for(int j=1;j<n;j++)
res[i][j]=res[i-1][j]+res[i][j-1];
return res[m-1][n-1];
}
};