@Override
public int pop() {
// TODO Auto-generated method stub
ListNode temp = head;
head = head.next;
return temp.getVal();
}
@Override
public void push(int val) {
// TODO Auto-generated method stub
ListNode current = new ListNode(val);
if (head == null) {
head = current;
} else {
ListNode iterNode = head;
while (iterNode.next != null) {
iterNode = iterNode.next;
}
iterNode.next = current;
}
}
@Override
public int peek() {
// TODO Auto-generated method stub
return head.getVal();
}