ATM小程序

//模拟ATM系统，固定账户：123，固定密码：123
import java.util.*;
public class Atm{
 public static void main(String[] args){
  final int USER=123;
  final int PWD=123;
  double money=2000,getMoney=0,saveMoney=0;
  int counter=0;
              boolean flag1=true,flag2=true;
             //登陆界面信息
  while(flag1){
   Scanner s=new Scanner(System.in);
   System.out.print("请输入账号："); 
   int user=s.nextInt();
   System.out.print("请输入密码："); 
   int password=s.nextInt();
   if(PWD!=password||USER!=user){
    counter++;
                     System.out.println("账户或密码错误！");
   }else{
    flag1=false;
   }   
   if(counter>3){
    flag1=false; 
   }
  }
  //登陆之后结果显示
  if(counter>3){
   System.out.println("本卡已锁！");
  }else{
   while(flag2){
   Scanner s=new Scanner(System.in);
   System.out.println("登陆成功请选择服务项目\n1=取款 2=存款 3=查询 4=退出");
                     int i=s.nextInt();
   System.out.print("\n");
   if(i==1){
    System.out.print("输入取款金额：");
    getMoney=s.nextDouble();
    money-=getMoney;
    System.out.println("取款成功。");
    }else if(i==2){
     System.out.print("输入存款金额：");
     saveMoney=s.nextDouble();
     money+=saveMoney;
     System.out.println("存款成功。");
    }else if(i==3){
     System.out.println("账户为："+USER+"\n余额为："+money+"\n");
    }else if(i==4){
     System.out.println("退出登陆。");
     flag2=false;
    }else{
     System.out.println("输入错误，请输入1-4的整数。\n");
     }
   }
   }
 }
}