public boolean addAll(CompactIntSet ints) {
        int oldSize = size();
        bitSet.or(ints.bitSet);
        return oldSize != size();
    }
public boolean addAll ( CompactIntSet ints ) { int oldSize = size ( ) ; bitSet . or ( ints . bitSet ) ; return oldSize != size ( ) ; }
Adds to this set all of the elements that are contained in the specified
{@code CompactIntSet} if not already present, using an {@code CompactIntSet}-optimized
process.