c语言代码解决问题

解题思路:

注意事项:

参考代码:

#include<stdio.h>

double f(int x)

{

    double c;

    if (x == 1)

        c = 1.0;

    else if (x == 2)

        c = 1.0;

    else

        c = f(x - 1) + f(x - 2);

    return c;

}

int main()

{

    long long int n;

    scanf("%lld", &n);

    if (n < 20)

    {

        printf("%.8lf", f(n) / f(n + 1));

    }

    else

        printf("0.61803399");

    return 0;

}