Question

I have two set of integers(i.e. first one is: 2,3,4,5 and second one is 1,2,3,6). How can I found the addition numbers array(1,6) and subtracted numbers array(4,5)? I said collection but I keep them at Set however if you have any other idea, I can use it too. I will keep addition numbers and subtracted numbers within different collections too.

Answer 1

I assume you mean elements in one set but not the other.

Set<Integer> first = new LinkedHashSet<Integer>(Arrays.asList(2,3,4,5));
Set<Integer> second = new LinkedHashSet<Integer>(Arrays.asList(1,2,3,6));
Set<Integer> addition = subtract(first, second);
Set<Integer> subtracted = subtract( second, first);

public static <T> Set<T> subtract(Set<T> set1, Set<T> set2) {
    Set<T> ret = new LinkedHashSet<T>(set1);
    ret.removeAll(set2);
    return ret;
}