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.
题意:一个机器人位于矩阵的左上角,它只能向右或向下走,问走到右下角的路径数。思路:简单的dp
class Solution { public: int uniquePaths(int m, int n) { vector<vector<int> > f(m, vector<int>(n)); for (int i = 0; i < n; i++) f[0][i] = 1; for (int i = 0; i < m; i++) f[i][0] = 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]; } };
原文:http://blog.csdn.net/u011345136/article/details/44645887