import java.util.*;

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


public class Main {
    static Scanner in = new Scanner(System.in);
    static PrintWriter out = new PrintWriter(System.out);
    
    static BigInteger ans[] = new BigInteger[220];
    public static void main(String args[]) {
        ans[1] = BigInteger.ONE;
        ans[0] = BigInteger.ONE;
        for(int i = 2; i <= 200; i ++) ans[i] = ans[i - 1].add(ans[i - 2]);
        
        while(in.hasNext()) {
            int n = in.nextInt();
            if(n == 0) out.println();
            else out.println(ans[n]);
            out.flush();
        }

    }
    
    static class pii implements Comparable<pii> {  
        int X, Y;  
        pii(int X, int Y) {  
            this.X = X;  
            this.Y = Y;  
        }  
        public int compareTo(pii a) {  
            if(this.X - a.X != 0) return this.X - a.X;  
            else return this.Y - a.Y;  
        }  
    }  
}