leetcode-Unique Paths

Difficulty: Medium

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