public synchronized void service() {
		while ( input == null ) {
			try {
				wait();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
		
		if (input % 2 == 0) {
			result = "even";
		} else {
			result = "odd";
		}
		
		notify();
		
		input = null;
	}