public static void main(String[] args) {
Deque<Integer> di = new Deque<Integer>();
fillTest(di);
print(di);
while (di.size() != 0) printnb(di.removeFirst() + " ");
print();
fillTest(di);
while (di.size() != 0) printnb(di.removeLast() + " ");
}
static void fillTest(Deque<Integer> deque) {
for (int i = 20; i < 27; i++) deque.addFirst(i);
for (int i = 50; i < 55; i++) deque.addLast(i);
}