public void show_menu() throws Exception{
		int menu;
		System.out.println("------------------------------");
		System.out.println("1. α");
		System.out.println("2. ȸ");
		System.out.println("3. ");
		System.out.println("------------------------------");
		System.out.print("޴ Է:");
		menu = scan.nextInt();

		switch(menu){
		case 1:
			login();
			//α
			break;
		case 2:
			join();
			//ȸ
			break;
		case 3:
			the_end();
			//
			break;
		}
	}