import java.util.*;

class Fibo1 {

    static final Scanner input = new Scanner(System.in);

    static long fibo(int n)
    {
        if (n <= 1)
            return n;               // 0 ou 1
        else
            return fibo(n - 2) + fibo(n - 1);
    }

    public static void main(String[] args) {
        int n;
        System.out.print("n? ");
        n = input.nextInt();
        System.out.println("F(" + n + ") = " + fibo(n));
    }
}