View Code of Problem 20

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.StreamTokenizer;


public class Main {
	public static void main(String[] args) throws IOException {
		BufferedReader bf =new BufferedReader(new InputStreamReader(System.in));
		String s;
		while( (s = bf.readLine()) != null) {
			int x = Integer.valueOf(s);
			if( x%3 ==0 ) {
				System.out.println("No");
			}else {
				System.out.println("Yes");
			}
		}

	}
	
}