[LeetCode] Unique Paths

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) 
    {
        int paths[m][n];
        for(int i=0;i<m;i++) paths[i][0] = 1;
        for(int j=0;j<n;j++) paths[0][j] = 1; 
        
        for(int i=1;i<m;i++)
        {
            for(int j=1;j<n;j++)
            {
                paths[i][j] = 
                paths[i-1][j] + paths[i][j-1];
            }
        }
        return paths[m-1][n-1];
    }
}