public void remove(int data) {
if (size == 0) {
throw new java.util.EmptyStackException();
}
for (NodeBi p = head; p.next != null; p = p.next) {
if (p.next.data == data) {
p.next = p.next.next;
size--;
break;
}
}
}
public void add(int data) {
NodeBi curr = new NodeBi(data);
if (tail == null) {
// since circular head and tail are the same
tail = new NodeBi(data);
head = tail;
size++;
} else {
// update tail
tail.next = curr;
curr.prev = tail;
tail = curr;
// maintain circularity
head.prev = tail;
tail.next = head;
size++;
}
}
