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<int> ivec(n); vector<vector<int>> f(m, ivec); for (int ki=0;ki<m;ki++) { f[ki][0]=1; } for (int kj=0;kj<n;kj++) { f[0][kj]=1; } for (int i=1;i<m;i++) { for (int j=1;j<n;j++) { f[i][j]=f[i-1][j]+f[i][j-1]; } } return f[m-1][n-1]; } };