Find numbers divisible by 3 in an ArrayList

Question

I am doing this for pure fun since I'm exploring into ArrayLists. I know how to use the modulus operator to check if it's divisible by 3. But, have know clue on how to use it with an arrayList.

public static void main(String[] args) {

    //Print out only a set of numbers divisible by 3 from an array.

    ArrayList<Integer> division = new ArrayList<Integer>();

    //Add a set of numbers.
    Division.add(10);
    Division.add(3);
    Division.add(34);
    Division.add(36);
    Division.add(435);
    Division.add(457);
    Division.add(223);
    Division.add(45);
    Division.add(4353);
    Division.add(99);


    //How can I fix the logic below?
    if(Division.get() % 3 == 0)

}

}

Answer 1

You need to loop over the items in your list, for example, using the enhanced for loop syntax:

for (int i : Division) {
    if (i % 3 == 0) {
        System.out.println(i + " is divisible by 3");
    }
}

Note:

• You should apply the java naming conventions. In particular, variable names start in lower case (apart from constants): Division => division.
• And your division object is really a list of numbers, so numbers would probably be a better name.

More info about lists in the Java Tutorial.