// Problem B.java
import java.io.*;
import java.math.*;
import java.util.*;

public class Main {
    public static void main(String[] args) {
    
        Scanner cin = new Scanner(new BufferedInputStream(System.in));
    
        BigInteger[] res = new BigInteger[205];
        res[0] = BigInteger.valueOf(1);
        res[1] = BigInteger.valueOf(1);
        for(int i = 2; i < 205; i++) {
            res[i] = res[i-1].add(res[i-2]);
        }
        while(cin.hasNext()) {
            int n = cin.nextInt();
            System.out.println(res[n]);
        }
        cin.close();
    }
}