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.
public class Solution {
public int uniquePaths(int m, int n) {
if(m==0||n==0){
return 0;
}
int paths[] = new int [n];
paths[0] = 1;
for(int i = 0; i<m; i++){
for(int j = 1; j<n; j++){
paths[j] = paths[j-1] + paths[j];
}
}
return paths[n-1];
}
}
