import java.util.*;
import java.math.*;

public class Main {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int n;
        BigInteger f[] = new BigInteger[205];
        Scanner cin = new Scanner(System.in);
        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]);
        while(cin.hasNext()){
            n = cin.nextInt();
            if(n == 0) System.out.println("");
            else System.out.println(f[n]);
        }
    }

}