public static void main(String[] argv) {
		if (argv.length != 1) {
			System.out.print("server or client?\n");
			return;
		}
		
		if (argv[0].equals("s")) {
			Server s = new Server();
			s.run();
		} else if (argv[0].equals("c")) {
			Client c = new Client();
			c.run();
		}
	}