Question

我正在为CS课程开发这个程序，并希望用户输入每个硬币的金额，向他们显示所述金币数量的金额值，然后将每个输出的钱加起来。

到目前为止我所拥有的东西允许某人为每种类型的硬币输入一笔钱，并显示许多硬币的金额，但我似乎无法弄清楚如何添加所有的金钱价值在末尾。我需要一个单独的方法来调用每种方法返回的所有金额。任何帮助，将不胜感激！这是我到目前为止所做的：

import java.util.*;

public class Coins {
  public static final Scanner CONSOLE = new Scanner(System.in);

  public static void main(String[] args) {
    quarterDollarAmount( );
    dimeDollarAmount( );
    nickelDollarAmount( );
    pennyDollarAmount( );
  }

  public static void quarterDollarAmount( ) {
    System.out.print("Enter the number of quarters: ");
    int quarterAmount = CONSOLE.nextInt( );
    double amount = quarterAmount * 0.25;
    System.out.println(quarterAmount + " quarter are $" + amount);
  }

  public static void dimeDollarAmount( ) {
    System.out.print("Enter the number of dimes: ");
    int dimeAmount = CONSOLE.nextInt( );
    double amount = dimeAmount * 0.1;
    System.out.println(dimeAmount + " dimes are $" + amount);
  }

  public static void nickelDollarAmount( ) {
    System.out.print("Enter the number of nickels: ");
    int nickelAmount = CONSOLE.nextInt( );
    double amount = nickelAmount * 0.05;
    System.out.println(nickelAmount + " nickels are $" + amount);
  }

  public static void pennyDollarAmount( ) {
    System.out.print("Enter the number of pennies: ");
    int pennyAmount = CONSOLE.nextInt( );
    double amount = pennyAmount * 0.01;
    System.out.println(pennyAmount + " pennies are $" + amount);
  }
}

好的，所以我用各自的硬币类型改变了所有的方法：

 public static double pennyDollarAmount( ) {
    System.out.print("Enter the number of pennies: ");
    int pennyAmount = CONSOLE.nextInt( );
    double amount = pennyAmount * 0.01;
    System.out.println(pennyAmount + " pennies are $" + amount);
    return amount;
  }

并添加了方法：

public static double totalDollarAmount( ) {
    double quarters = quarterDollarAmount();
    double dimes = dimeDollarAmount();
    double nickels = nickelDollarAmount();
    double pennies = pennyDollarAmount();
    int total = quarters + dimes + nickels + pennies;
    System.out.println("Total amount is $" + total);
  }
}

但是现在，编译器输出说（我出于显而易见的原因取出了我的系统详细信息）：

1 error found:
File: /Users//Documents/Semester 2/CS/Coins.java  [line: 51]
Error: /Users//Documents/Semester 2/CS/Coins.java:51: possible loss of precision
found   : double
required: int

并将光标置于+ in + pennies之前;知道这意味着什么吗？

Answer 1

您需要return amount;并将所有与资金相关的功能的回复类型从void更改为double。

public static double quarterDollarAmount( ) {
    System.out.print("Enter the number of quarters: ");
    int quarterAmount = CONSOLE.nextInt( );
    double amount = quarterAmount * 0.25;
    System.out.println(quarterAmount + " quarter are $" + amount);
    return amount;
}

然后在调用函数时捕获变量中的返回值。

double quarters = quarterDollarAmount();
...
double pennies = pennyDollarAmount();

然后，您可以将存储在这些变量中的值一起添加到您想要的结果中。

double total = quarters + ... + pennies;

Answer 2

您可以设置global变量并将计算结果设置为此variable并添加所有变量。

或

将函数的返回类型从void更改为double并执行总和。

Answer 3

你需要一个类变量

public static double totalAmount=0.0

将使用代码

在每个方法中更新

totalAmount += amount;。

然后

    public static void getTotalAmount() {
       System.out.println(" Total Amount of coins are $" + totalAmount);
    }

将完成这项工作。

如何在方法中添加用户输入的所有输出？

3 个答案: