import java.util.Scanner;
import java.math.BigInteger;
public class Main{
    public static void main(String[]args){
        BigInteger a[]=new BigInteger[221];
         a[1]=BigInteger.valueOf(1);
    a[2]=BigInteger.valueOf(2);
        int i;
        for(i=3;i<=211;i++){
        a[i]=BigInteger.valueOf(0);
            a[i]=a[i-1].add(a[i-2]);
        }
        Scanner cin=new Scanner(System.in);
        int n;
        while(cin.hasNext()){
        n=cin.nextInt();
        System.out.println(a[n]);
        }


    }
}