public void testAddElements(int size) {
List<Integer> src = makeRandomNumberList(size);
SinglyLinkedList l = new SinglyLinkedList();
copy(src, l);
ListIterator it = src.listIterator(src.size());
while (it.hasPrevious()) assertEquals(it.previous(), l.pop_back());
}
private static void copy(List<Integer> from, SinglyLinkedList to) {
for (Integer n : from) to.push_back(n);
}