Java - 运行总计（使用do while和else else语句）

Question

我不是很熟悉使用Java的运行总数，因为我最近开始使用它。我必须显示并持有银行余额的总额，出于某种奇怪的原因，它重置为100，这正是我宣布的开始时的情况。有没有办法让我在每次循环时都停止银行余额的重置？

public static void main(String args[]) 
{ 
    Scanner sc = new Scanner(System.in); 
    int choice, totBal = 0, totWith = 0, totDep = 0; 
    double with, remBal = 0, deposit, bankBal = 100; 
    char reply = 0; 

    do 
    { 
     System.out.println(""); 
     System.out.println("Bank online\n"); 
     System.out.println("1. Withdraw"); 
     System.out.println("2. Deposit"); 
     System.out.println("3. Balance"); 
     System.out.println("4. Account Details"); 
     System.out.println("5. Exit\n"); 
     System.out.print("Enter your choice: "); 
     choice = sc.nextInt(); 

     if(choice == 1) 
     { 
      System.out.print("How much do you wish to withdraw?\n"); 
      with = sc.nextInt(); 
      remBal = bankBal - with; 
      System.out.println("Your new balance is: " + remBal); 
      totWith++; 
     } 
     else if(choice == 2) 
     { 
      System.out.print("How much do you wish to deposit?\n"); 
      deposit = sc.nextInt(); 
      remBal = remBal + deposit; 
      System.out.println("Your new balance is: " + remBal); 
      totDep++; 
     } 
     else if(choice == 3) 
     { 
      System.out.println("Your balance is: " + remBal); 
      totBal++; 
     } 
     else if(choice == 4) 
     { 
      System.out.println("You made " + totWith + " withdrawls from your account."); 
      System.out.println("You made " + totDep + " deposits to your account."); 
      System.out.println("You made " + totBal + " balance checks on your account."); 
     } 
     else if(choice == 5) 
     { 

     } 

     System.out.println(""); 
     System.out.print("Do you want to enter another option?(y/n): "); 
     reply = sc.next().charAt(0); 

    }while(reply == 'Y' || reply == 'y'); 

    System.out.println("Thank you and goodbye!"); 
} 

}

另外，我觉得我有太多的变数。我怎样才能减少这些？

Answer 1

你的问题是与下面的语句：

double with, remBal = 0, deposit, bankBal = 100; 

这里你正在初始化remBal为0，而当一个存款金额/检查平衡你这样做：

remBal = remBal + deposit;//you use remBal for blaance check 

所以它会先尝试尝试添加0与说$ 100这将是100而bankBal是100它应该是100.所以初始化remBal相同于bankBal（或只使用一个变量为bankBalance，即任一）。

Answer 2

您在程序开始时将bankBal值设置为100。 在做提款，你总是这样

remBal = bankBal - with 

将总是等同于

remBal = 100 - with 

，因为你永远不会改变bankBal，以反映每个循环后更新的余额。 一种方法来解决这是完全消除

bankBal 

变量和只需将

remBal 

变量设置为所需的起始值。 上述撤军计算最后变成

remBal = remBal - with 

Answer 3

一两件事你可以做的就是实现开关的情况下调用特定于Depost方法，撤柜，等这方面的例子大致是：

public static void main(String[] args) { 
    Scanner input = new Scanner(System.in); 
    System.out.println("Please Enter what you would like to do: "); 
    String enterPrompt = input.next(); 
    int options = 5; 
    switch (options) { 
     case 1: enterPrompt = "Deposit"; 
       doDeposit(); 
       break; 
     case 2: enterPrompt = "Withdrawel"; 
       doWithdrawel(); 
       break; 
     case 3: enterPrompt = "Balance"; 
       viewBalance(); 
       break; 
     case 4: enterPrompt = "Account Details"; 
       viewAccount(); 
       break; 
     case 5: enterPrompt = "Exit"; 
       System.exit(1); 
       break; 
    } 
    public void doDeposit(){ 
    //local variables here 
    //Do stuff 
     } 
    public void doWithdrawel(){ 
    //local variables here 
    //Do stuff 
    } 
    public void viewBalance(){ 
    //local variables here 
    //Do stuff 
    } 
    public void viewAccount(){ 
    //local variables here 
    //Do stuff 
    } 

}