AC的代码如下:
#include <iostream>
using namespace std;
int main()
{
unsigned long long int s[52];
s[1] = 1;
s[2] = 1;
for (int i = 3; i < 52; i++)
{
s[i] = s[i - 1] + s[i - 2];
}
int n;
while (cin >> n)
{
cout << s[n + 1] << endl;
}
return 0;
}