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?
class Solution {
public:
int uniquePaths(int m, int n) {
int buf[m][n];
for (int i = 0; i < m; i++)
{
buf[i][0] = 1;
}
for (int i = 0; i < n; i++)
{
buf[0][i] = 1;
}
for (int i = 1; i < m; i++)
{
for (int j = 1; j < n; j++)
{
buf[i][j] = buf[i-1][j] + buf[i][j-1];
}
}
return buf[m-1][n-1];
}
};