package TcmStudy.day06; import java.util.Scanner; public class BreakDemo03 { public static void main(String[] args) { Scanner input = new Scanner(System.in); int balance = 100; //通过一个布尔值 实现 循环结束 boolean flag = true; while (flag) { //实现一个银行 ATM机的操作 System.out.println("=====ATM====="); System.out.println("1.取款"); System.out.println("2.存款"); System.out.println("3.金额"); System.out.println("4.结束"); System.out.println("请选择"); int select = input.nextInt(); switch (select) { case 1: //取款 System.out.println("请输入取款金额"); double money = input.nextDouble(); if (money <= balance) { balance -= money; } else { System.out.println("余额不足");} break; case 2: //存款 System.out.println("请输入存款金额"); money = input.nextDouble(); balance += money; break; case 3: //显示金额 System.out.println("余额是:" + balance); break; case 4: // 结束循环 flag = false; break; //结束while循环 } } } }