题解 | #跳台阶扩展问题#
跳台阶扩展问题
https://www.nowcoder.com/practice/953b74ca5c4d44bb91f39ac4ddea0fee
#include <bits/stdc++.h>
using namespace std;
int main() {
int n;
cin >> n;
cout << (long long) (1 << n - 1) << endl;
return 0;
}
f(n) = f(n-1) + f(n-2) + ... + f(1)
f(n-1) = f(n-2) + f(n-3) + ... + f(1)
f(n) = 2f(n-1)
f(n)/f(n-1) = 2
