public void Remove(DequeNode <TValue> node)
{
if (node == null)
{
throw new ArgumentNullException(nameof(node));
}
if (this.front == this.back)
{
this.front = this.back = null;
}
else if (this.front == node)
{
this.front = this.front.right;
this.front.left = null;
}
else if (this.back == node)
{
this.back = this.back.left;
this.back.right = null;
}
else
{
node.left.right = node.right;
node.right.left = node.left;
}
node.left = node.right = null;
}
public override string ToString()
{
StringBuilder stringBuilder = new StringBuilder();
for (DequeNode <TValue> node = this; node != null; node = node.right)
{
stringBuilder.Append(node.value + " ");
}
return(stringBuilder.ToString());
}
public DequeNode <TValue> PopBack()
{
DequeNode <TValue> node = this.back;
if (this.front == this.back)
{
this.front = this.back = null;
}
else
{
this.back = node.left;
this.back.right = null;
}
node.left = node.right = null;
return(node);
}
public void PushFront(DequeNode <TValue> node)
{
if (node == null)
{
throw new ArgumentNullException(nameof(node));
}
if (this.front == null)
{
node.left = node.right = null;
this.front = this.back = node;
}
else
{
node.left = null;
node.right = this.front;
this.front.left = node;
this.front = node;
}
}
private void Visit(TPage page)
{
if (this.visitDictionary.ContainsKey(page))
{
this.visitList.Remove(this.visitDictionary[page]);
this.visitList.PushFront(this.visitDictionary[page]);
return;
}
if (this.historyLength == this.historyCapacity)
{
DequeNode <TPage> node = this.visitList.PopBack();
this.visitDictionary.Remove(node.value);
this.historyLength -= 1;
}
this.visitDictionary[page] = new DequeNode <TPage> {
value = page
};
this.visitList.PushFront(this.visitDictionary[page]);
this.historyLength += 1;
}