假设你正在爬楼梯,需要n步你才能到达顶部。但每次你只能爬一步或者两步,你能有多少种不同的方法爬到楼顶部?
样例
Example 1:
Input: n = 3
Output: 3
Explanation:
1) 1, 1, 1
2) 1, 2
3) 2, 1
total 3.
Example 2:
Input: n = 1
Output: 1
Explanation:
only 1 way.
class Solution {
public:
/**
* @param n: An integer
* @return: An integer
*/
int climbStairs(int n)
{
// write your code here
int dp[n+1] = {0};
dp[0] = 0;
dp[1] = 1;
dp[2] = 2;
for(int i = 3; i <= n; i++)
{
dp[i] = dp[i-1] + dp[i-2];
}
return dp[n];
}
};