java中循环小Demo练习分享

//倒三角
	private static void delta() {
		for (int i = 0; i < 10; i++) {
			 
			for (int j = 0; j < 10-i; j++) {
				System.out.print("#");
			}
			System.out.println();
		}
	}
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//猜数字
	private static void romTest() {
		Scanner scanner = new Scanner(System.in);
		
		Random rdom  = new Random();
		int rom = rdom.nextInt(101);	//生产随机数
		int count = 10;	//决定猜测次数
		while (true) {
			count--;	//控制猜测次数
			System.out.println("请输入您猜测的数字");
			int inRom = scanner.nextInt();
			if (count == 0) {	
				System.out.println("猜错没有机会了，退出系统");
				break;
			}
			if (inRom==rom) {
				System.out.println("对了");
				break;
			}else if (inRom<rom) {
				System.out.println("小了，继续猜测还有"+count+"次机会");
			}else if (inRom>rom) {
				System.out.println("大了，继续猜测还有"+count+"次机会");
			}
			
		}
		scanner.close();
	}
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//登录模拟
	private static void logSys() {
		Scanner scanner = new Scanner(System.in);
		
		int count = 3;
		for (int i = 0; i < 3; i++) {
			System.out.println("请输入密码");
			String string = scanner.nextLine();
			count--;
			System.out.println(string);
			if (string.equals("123456")) {
				System.out.println("登录成功");
				break;
			}else if (count ==0) {
				
				System.out.println("抱歉，机会使用完了，已退出系统");
			}else {
				System.out.println("登录失败重新输入，您还有"+count+"次机会");
			}
		}
		scanner.close();
	}
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