如何在 Java 中获取硬币的数量

Question

我有我的代码，用户输入一定数量的钱，输出显示二十、十、五、一、四分之一、一角钱、镍币和便士的数量，但我希望用户输入一定数量的硬币（例如 36）并获得 ONLY 硬币的数量，即 36 美分。意思是我应该得到 1 个季度、1 角钱和 1 便士。请有人帮我解决这个问题。多谢！

注意：
十进制格式类不是必需的

这是我的代码：

import java.util.Scanner;
import java.text.DecimalFormat;
public class Compu
{ 
public static void main(String[] args)
{
   Scanner input = new Scanner(System.in);
   DecimalFormat decimalFormat = new DecimalFormat("0.00");
    System.out.println("Please Enter an amount of Money:");       
    double change = input.nextDouble();

    int dollars = (int)change;
    int twenties = dollars / 20;
    int dollars1 = dollars % 20;
    int tens = dollars1 / 10;
    int dollars2 = dollars % 10;
    int fives = dollars2 / 5;
    int dollars3 = dollars % 5;
    int ones = dollars3;
    String moneyString = decimalFormat.format(change);
    String changeString = Double.toString(change); 
    String[] parts = moneyString.split("\.");
    String part2 = parts[1]; 
    double cents5 = Double.parseDouble(part2);
    int cents = (int)cents5;
    int quarters = cents / 25;
    int cents1 = cents % 25;
    int dimes = cents1 / 10;
    int cents2 = cents % 10;
    int nickels = cents2 / 5;
    int cents3 = cents % 5;
    int pennies = cents3;
    System.out.println("Input entered by user: " + "$" + moneyString);

    System.out.println(twenties + " Twenties");
    System.out.println(tens + " Tens");
    System.out.println(fives + " Fives");
    System.out.println(ones + " Ones");
    System.out.println(quarters + " Quarters");
    System.out.println(dimes + " Dimes");
    System.out.println(nickels + " Nickels");
    System.out.println(pennies + " Pennies");
  }
}

Answer 1

模运算符是你的朋友：

public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.println("Please enter amount in cents");
    double cents = input.nextInt();
    int numQuarters = cents / 25;
    int numDimes    = (cents % 25) / 10;
    int numNickels  = ((cents % 25) % 10) / 5;
    int numPennies  = ((cents % 25) % 10) % 5;
    System.out.println(quarters + " Quarters");
    System.out.println(dimes    + " Dimes");
    System.out.println(nickels  + " Nickels");
    System.out.println(pennies  + " Pennies");
}

Answer 2

为此，请完全删除程序中处理美元的部分，并将用户输入直接提供给"美分"。

另外，这部分：

int cents = (int)cents5;
int quarters = cents / 25;
int cents1 = cents % 25;
int dimes = cents1 / 10;
int cents2 = cents % 10;
int nickels = cents2 / 5;
int cents3 = cents % 5;
int pennies = cents3;

将不准确（在少数情况下。不是全部），因为您不会更改"美分"的值。因此，如果您输入"36"，它将返回 1 四分之一 （25）、1 角硬币 （35）、1 镍 （40） 和 1 便士 （41）。

若要避免这种情况，请使用以下代码：

int cents = (int)cents5;
int quarters = cents / 25;
int cents1 = cents % 25;
int dimes = cents1 / 10;
int cents2 = cents1 % 10;
int nickels = cents2 / 5;
int cents3 = cents2 % 5;
int pennies = cents3;