斐波那契数列

import java.util.Scanner;


public class Fabenacii 
{
	public static void main(String args[])
	{
		int []a=new int [1024];
		a[0]=1;
		a[1]=1;
		for(int i=2;i<1024;i++)
		{
			a[i]=a[i-1]+a[i-2];
		}
		Scanner sc=new Scanner(System.in);
		int x=sc.nextInt();
		System.out.println(a[x]);
	}
}