Help!

[melinko928]

import javax.swing.JOptionPane;
public class Divideby3
{
    public static void main(String args[])
    {

        int n1, n2, n2;
        int divisby3 = 0;

        String s1 = JOptionPane.showInputDialog("Enter first number ");
        n1 = Integer.parseInt(s1);
        s1 = JOptionPane.showInputDialog("Enter second number ");
        n2 = Integer.parseInt(s1);
        s1 = JOptionPane.showInputDialog("Enter third number ");
        n3 = Integer.parseInt(s1);

        if ( n1/3 != double)
        {
            divisby3 += 1;
        }
        if ( n2/3 != double)
        {
            divisby3 += 1;
        }
        if ( n3/3 != double)
        {
            divisby3 += 1;
        }

        JOptionPane.showMessageDialog(null,"There are " + divisby3 + " numbers divisible by three.");
    }
}

What do i do?
the original question is :

5. Write an application that inputs three numbers from a user and displays how many of the numbers are divisible by 3.

[Fubarable]

What do i do?

First of all (and it should seem obvious): tell us exactly what's wrong.

[melinko928]

\CIT270\Divideby3.java:17: error: '.class' expected
if ( n1/3 != double);
^
Z:\CIT270\Divideby3.java:21: error: '.class' expected
if ( n2/3 != double)
^
Z:\CIT270\Divideby3.java:25: error: '.class' expected
if ( n3/3 != double)
^
3 errors

Tool completed with exit code 1

[melinko928]

Thats the errors I am getting

[Iron Lion]

if ( n1/3 != double) { ... }

I see what you're trying to do here, but it doesn't work that way:
1: You can't test whether a variable is a primitive type by comparing it to the name of that type. If you're working with objects you can use the instanceof operator, but that won't help you here.
2: Since n1 has been declared as int, n1/3 will also be int. If n1 is 7, then n1/3 will evaluate to 2, with the remainder of 1 being discarded.

Instead, use the modulus operator (%) to test for the remainder which results from integer division.

[Fubarable]

OK, what are you trying to do with this line?

if ( n1/3 != double)

double is the name of a type, so this makes no sense.

[melinko928]

so....

 if (n1/3 != %)

... im not sure if i understand?

[Iron Lion]

Assignment, Arithmetic, and Unary Operators (The Java™ Tutorials > Learning the Java Language > Language Basics)

[melinko928]

sorry, i just am not sure of how to test if a number will be evenly divisible by another, so i thought if i tested it not being equal to a decimal it may work....

[melinko928]

ok i think i got it...

if ( n153 == 0)
		{
			divisby3 += 1;
		}
		if ( n2%3 == 0)
		{
			divisby3 += 1;
		}
		if ( n3%3 == 0)
		{
			divisby3 += 1;
		}

right?

[Iron Lion]

Your calculation to check for divisibility by 3 is fine now, although I don't see where n153 is declared or why it needs to be 0.

Edit: just noticed it's a typo for n1%3. Yep, that'll work, but your code could benefit from arrays and/or loops instead of writing the same condition three times for three different variables.

[melinko928]

import javax.swing.JOptionPane;
public class Divideby3
{
public static void main(String args[])
{

	int n1, n2, n3;
	int divisby3 = 0;

	String s1 = JOptionPane.showInputDialog("Enter first number ");
	n1 = Integer.parseInt(s1);
	s1 = JOptionPane.showInputDialog("Enter second number ");
	n2 = Integer.parseInt(s1);
	s1 = JOptionPane.showInputDialog("Enter third number ");
	n3 = Integer.parseInt(s1);

	if ( n1%3 == 0)
	{
		divisby3 += 1;
	}
	if ( n2%3 == 0)
			{
		divisby3 += 1;
	}
	if ( n3%3 == 0)
	{
		divisby3 += 1;
	}

JOptionPane.showMessageDialog(null,"There are " + divisby3 + " numbers divisible by three.");

It works... you rock iron lion!!!
thanks so much

[melinko928]

Your calculation to check for divisibility by 3 is fine now, although I don't see where n153 is declared or why it needs to be 0.

it was a typo! :)