How can I make it so my while-loop only prints even numbers? Java Eclipse IDE

% is an arithmetic operator, it is called MODULO.
Modulo operator returns the remainder of 2 numbers. In this case, we use a modulo to find out whether a number is even or odd.

odd%2 returns 1

even%2 returns 0

The while loop loops through the first 20 elements. So we put an if statement before printing the element. If the counter is an even number i.e (counter%2 == 0) we print that.

This is the code that prints even numbers:

        int counter = 0;
        System.out.println("Part 2 - Even Numbers");
        while (counter <= 20)
        {
            if (counter%2 == 0){
                System.out.printf("%d ", counter);
            }
            counter++;
        } // end while loop

This can also be done without using MODULO operator:

        int counter = 0;
        System.out.println("Part 2 - Even Numbers");
        while (counter <= 20)
        {
            System.out.printf("%d ", counter);
            counter+=2;
        } // end while loop

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