LeetCode 62. Unique Paths

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?

线性动归

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