Question

此程序进行更改，除了$ 1.16，为什么这不能正确处理？

public class Change {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.println("Enter Change: ");
        double change = in.nextDouble()*100;
        int dollars = Math.round((int)change/100);
        change=change%100;
        int quarters = Math.round((int)change/25);
        change=change%25;
        int dimes = Math.round((int)change/10);
        change=change%10;
        int nickels = Math.round((int)change/5);
        change=change%5;
        int pennies = Math.round((int)change/1);

        System.out.println("Dollars: " + dollars);
        System.out.println("Quarters: " + quarters);
        System.out.println("Dimes: " + dimes);
        System.out.println("Nickels: " + nickels);
        System.out.println("Pennies: " + pennies);
    }
}

我认为这是一个截断的问题，因为当我在下面的一段代码中使用.9时，它可以工作：

int pennies = Math.round((int)change/.9);

Answer 1

问题是变化是双重的。当我运行它时，我打印出更改之前的便士声明这是打印的：0.9999999999999858。当它被转换为int时，它变为0.所以0/1为0.不要使用双重模数除法。输入1.16时，返回1.1599999999999999999999999999999。尝试将输入四舍五入。

        Scanner in = new Scanner(System.in);
        System.out.println("Enter Change: ");
        int change = (int)(Math.ceil(in.nextDouble()*100));
        int dollars = Math.round((int)change/100);
        change=change%100;
        int quarters = Math.round((int)change/25);
        change=change%25;
        int dimes = Math.round((int)change/10);
        change=change%10;
        int nickels = Math.round((int)change/5);
        change=change%5;
        int pennies = Math.round((int)change/1);

        System.out.println("Dollars: " + dollars);
        System.out.println("Quarters: " + quarters);
        System.out.println("Dimes: " + dimes);
        System.out.println("Nickels: " + nickels);
        System.out.println("Pennies: " + pennies);

此代码有效。

改变计划不能使用$ 1.16

1 个答案: