public void PushFront(T key)
{
var node = new DsLinkedListNode <T> {
Key = key
};
node.Next = _head;
_head = node;
if (_tail == null)
{
_tail = _head;
}
}
public void PushBack(T key)
{
var node = new DsLinkedListNode <T>
{
Key = key,
Prev = _tail
};
_tail = node;
if (_head == null)
{
_head = _tail;
}
}
public T PopBack()
{
if (_tail == null)
{
throw new InvalidOperationException();
}
var node = _tail;
_tail = _tail.Prev;
if (_tail == null)
{
_head = null;
}
else
{
_tail.Prev = null;
}
return(node.Key);
}
public T PopFront()
{
if (_head == null)
{
throw new InvalidOperationException();
}
var node = _head;
_head = _head.Next;
if (_head == null)
{
_tail = null;
}
else
{
_head.Prev = null;
}
return(node.Key);
}