9、剑指offer--变态跳台阶

 1 #include <iostream>
 2 using namespace std;
 3 class Solution {
 4 public:
 5     //fn=2^(n-1)
 6     int jumpFloorII(int number) {
 7         if(number <= 0)
 8             return 0;
 9         //fibN = 2^(n-1);
10         else if(number == 1)
11             return 1;
12         else
13             return 2*jumpFloorII(number-1);
14  
15     }
16 };
17 int main()
18 {
19     int n;
20     while(cin>>n)
21     {
22         Solution s;
23         cout<<"跳"<<n<<"级台阶需要步数："<<s.jumpFloorII(n)<<endl;
24     }
25     return 0;
26 }