import java.util.*;
import java.io.*;
import java.math.BigInteger;

public class Main {

    public static void main(String[] args) {
        // TODO 自动生成的方法存根
        Scanner in = new Scanner(System.in);
        BigInteger[] F = new BigInteger [500];
        F[1]=BigInteger.valueOf(1);
        F[2]=BigInteger.valueOf(2);
        for (int i=3;i<=200;i++)
        {
            F[i]=F[i-1].add(F[i-2]);
        }
        int T;
        while (in.hasNext())
        {
            T = in.nextInt(); 
            if (T == 0) System.out.println("\n");
            else System.out.println(F[T]);
        }

    }

}