java - 我被这个计算器程序困住了，我没有得到正确的答案

Question

这个问题已经有答案了:

Int division: Why is the result of 1/3 == 0? (19 个回答)

已关闭 3 年前。

我的编程类(class)希望我有这样的结局:

• 输入第一个数字!
• 9
• 输入第二个数字!
• 5
• 9 + 5 = 14
• 9 - 5 = 4
• 9 * 5 = 45
• 9/5 = 1.8 这就是问题所在，我编写的程序只给出 1.0 作为答案。我怎样才能让这个数字变成 1.8 而不是 1.0？

public class Nelilaskin {

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


        System.out.println("Enter the first number!");
        int first = Integer.valueOf(reader.nextLine());
        System.out.println("Enter the second number!");
        int second = Integer.valueOf(reader.nextLine());
        int plus = (first + second);
        int minus = (first - second);
        int multi = (first * second);
        double division = (first / second * 1.0);

        System.out.println(first + " + " + second + " = " + plus);
        System.out.println(first + " - " + second + " = " + minus);
        System.out.println(first + " * " + second + " = " + multi);
        System.out.println(first + " / " + second + " = " + division);


    }

}

Answer 1

考虑将第一个和第二个的数据类型替换为Float。并将结果也存储在浮点变量中，然后输出将是所需的。

float plus = (first + second);
float minus = (first - second);
float multi = (first * second);
float division = first / second;