import java.util.Scanner;

public class N534
{
	public static int k=0;
	public static int buf=0;


	public static void main(String[] args)
	{
		int X=0;
		Scanner sc=new Scanner(System.in);
		int n=sc.nextInt();
		//X=N534.fib(N534.fib(n))%(int)Math.pow(10, 9)+7;
		X=N534.fib(N534.fib(n));
		System.out.println(X);
	}

	public static int fib(int n)
	{
		int prefib=0;
		int fib=1;
		if(n==0)
		{return prefib;}
		if(n==1)
		{return fib;}

		for(int i=1;i<n;i++)
		{
		buf=fib;
		fib=prefib+fib;
		prefib=buf;
		}
		return fib;
	}

}