import java.math.BigInteger;
import java.util.Scanner;

public class Main{
    public static void main(String[] args){
        Scanner scan=new Scanner(System.in);
        BigInteger[] f=new BigInteger[201];
        f[0]=BigInteger.ONE;
        f[1]=BigInteger.ONE;
        for(int i=2;i<=200;i++){
            f[i]=f[i-1].add(f[i-2]);
        }
        int n;
        while(scan.hasNext()){
            n=scan.nextInt();
            System.out.println(f[n]);
        }
    }
}