当用户输入0时如何要求多个输入并停止？

Question

我的程序应该收到大量的钱，并将其转换为找零，但是当它收到0时，它应该停止请求输入并停止程序。

我所有的数学都是正确的，我只是在重复询问数字时遇到了问题。这是我目前拥有的：

public class Coins {

    public static int quarters;
public static int dimes;
public static int nickels;
public static int pennies;

    public static int Quarters(int TotalCoins) {
        quarters = (int) (TotalCoins / 25);
        TotalCoins %= 25;
        return quarters;
    }
    public static int Dimes(int TotalCoins){
        TotalCoins -= (quarters * 25);
        dimes = (int) (TotalCoins / 10);
        TotalCoins %= 10;
        return dimes;
}
    public static int Nickels(int TotalCoins){
        TotalCoins -= (dimes * 10) + (quarters * 25);
        nickels = (int) (TotalCoins / 5);
        TotalCoins %= 5;
        return nickels;
    }
    public static int Pennies(int TotalCoins){
        TotalCoins -= (nickels * 5 ) + (dimes * 10 ) + (quarters * 25);
        pennies = (int) (TotalCoins / 1);
        TotalCoins %= 1;
        return pennies;
    }
}

这是我的测试类（我很确定我的主要问题是）：

public class CoinsTester {
    public static void main(String[] args) {           
        Scanner kybd = new Scanner(System.in);

        if (kybd.nextInt() != 0){
            int changeMoney = kybd.nextInt();
            System.out.println("Quarters = " + Coins.Quarters(changeMoney) + "\nDimes = " + Coins.Dimes(changeMoney) + "\nNickels = " + Coins.Nickels(changeMoney) + "\nPennies = " + Coins.Pennies(changeMoney));              
        }
    }
}

任何帮助都会很棒。

编辑：有人告诉我，在一堂课上做整件事可能会更容易，如果是这样，那么任何这样做的建议也会很好。谢谢！！！
编辑：我忘了提到我应该能够输入所有数字，然后显示所有数字的输出。

Answer 1

你想要这样的东西：

Scanner kybd = new Scanner(System.in);

while (true) { 
    int changeMoney = kybd.nextInt();
    if (changeMoney == 0)
        break;

    // do stuff with changeMoney
}

也可以表示为for循环：

Scanner kybd = new Scanner(System.in);
for (int changeMoney = kybd.nextInt(); changeMoney != 0; changeMoney = kybd.nextInt()) {
    // do stuff with changeMoney 
}

虽然行数更少，但它使 for 循环行很长，但这可以通过使用更短的变量名来缓解：

Scanner in = new Scanner(System.in);
for (int i = in.nextInt(); i != 0; i = in.nextInt()) {
    // do stuff with i
}

Answer 2

您向用户询问了两次号码

• 一旦处于状态，
• 在您的if 语句中的第二个。

如果您想让用户再次写入另一个数字，您的if 似乎应该替换为循环。在这种情况下，您可以使用类似

Scanner kybd = new Scanner(System.in);
for (int changeMoney = -1; (changeMoney = kybd.nextInt()) != 0;){
    System.out.println("Quarters = " + Coins.Quarters(changeMoney) + "\nDimes = " + Coins.Dimes(changeMoney) + "\nNickels = " + Coins.Nickels(changeMoney) + "\nPennies = " + Coins.Pennies(changeMoney));
}

这种方法的优点是它很短，changeMoney 将是仅在循环内可用的局部变量。

Answer 3

首先，您的方法名称应该小写。其次，你需要一个循环——也许像这样

public static void main(String[] args) {
  Scanner kybd = new Scanner(System.in);

  while (kybd.hasNextInt()){ // will stop if the next input is not an int.
    int changeMoney = kybd.nextInt();
    if (changeMoney == 0) {
      break;
    }
    // Assuming you just rename them to "get" methods.
    System.out.println("Quarters = "
        + Coins.getQuarters(changeMoney) + "\nDimes = "
        + Coins.getDimes(changeMoney) + "\nNickels = "
        + Coins.getNickels(changeMoney)
        + "\nPennies = "
        + Coins.getPennies(changeMoney));
  }
}

Answer 4

把它改成这样。

 int changeMoney=0;
 while ( (changeMoney =kybd.nextInt()) != 0){           
     System.out.println("Quarters = " + Coins.Quarters(changeMoney) + "\nDimes = " + Coins.Dimes(changeMoney) + "\nNickels = " + Coins.Nickels(changeMoney) + "\nPennies = " + Coins.Pennies(changeMoney));    
 }

在@Bohemian 回答：很棒的代码。我的错忘记提及（对此感到抱歉）我 应该可以一次输入所有输入的数字，我该怎么做 你会说这个吗？

将输入存储在一个集合中，例如 List。

代码示例：

List<Integer> list = new ArrayList<>();          
while ( (int i =kybd.nextInt()) != 0){           
     list.add(i);
}
// Then loop again
for(Integer changeMoney : list){
     System.out.println("Quarters = " + Coins.Quarters(changeMoney) + "\nDimes = " + Coins.Dimes(changeMoney) + "\nNickels = " + Coins.Nickels(changeMoney) + "\nPennies = " +      Coins.Pennies(changeMoney)); 
}

Answer 5

看起来你只读了一次，你应该将scanner.nextInt()调用包装在一个while循环中，如果值为0则中断

while (kybd.hasNextInt()){
   int changeMoney = kybd.nextInt();
   if(changeMoney == 0)break;

   System.out.println("Quarters = " + Coins.Quarters(changeMoney) + "\nDimes = " + Coins.Dimes(changeMoney) + "\nNickels = " + Coins.Nickels(changeMoney) + "\nPennies = " + Coins.Pennies(changeMoney));

}