I'm stuck with this calculator program, I'm not getting the right answer

Question

My programming course wants me to have this kind of endcome:

Enter the first number!
9
Enter the Second number!
5
9 + 5 = 14
9 - 5 = 4
9 * 5 = 45
9 / 5 = 1.8 and this is the problem, the program I've written only gives me 1.0 as an answer. How can I get this number to be 1.8 not 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);


    }

}

You're performing int division and then multiplying by `1.0`. You could cast `first` or `second` to a double, or you can change the type of the variable to double. — khelwood, Mar 16 '20 at 11:42

score 2 · Answer 1 · answered Mar 16 '20 at 11:43

2

Consider replacing the data type for first and second as Float. And store the resultant in a float variable as well, then the output would be as required.

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

answered Mar 16 '20 at 11:43

Sagar Dhawan

37
1
7

1

Already tried this, but the course wants me to have the other answers as int values. If I change everything to float the outcome would be 14.0, 4.0, 45.0 and 1.8. – pakkis26 Mar 16 '20 at 11:47
2

Even if changing everything to `Float` is overkill _for now_, at least you know what to do if the next exercise is "Change your calculator to allow numbers with decimal points to be entered" (;->) – Kevin Anderson Mar 16 '20 at 11:53

Bashir · Accepted Answer · 2020-03-16T13:08:38.517

1

this is because you are dividing two int values, try to cast at least one of them to double..

   double division = (double)first / (double)second ;

edited Mar 16 '20 at 13:08

answered Mar 16 '20 at 11:42

Bashir

1,964
5
15
34

1

This was the problem! Thank you so much for helping! – pakkis26 Mar 16 '20 at 11:51
3

Note: only one cast is required – user85421 Mar 16 '20 at 12:27

I'm stuck with this calculator program, I'm not getting the right answer

2 Answers2