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

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