IEnumerator <T> IEnumerable <T> .GetEnumerator()
{
DoubleNode <T> current = _head;
while (current != null)
{
yield return(current.Data);
current = current.Next;
}
}
public IEnumerable <T> BackEnumerator()
{
DoubleNode <T> current = _tail;
while (current != null)
{
yield return(current.Data);
current = current.Previous;
}
}
public bool InsertAtHead(string n)
{
DoubleNode node = new DoubleNode();
node.Name = n;
node.next = head.next;
node.next.prev = node;
node.prev = head;
head.next = node;
count++;
return true;
}
public DoublyLinkedList()
{
head = new DoubleNode();
tail = new DoubleNode();
head.Name = "Head";
head.prev = null;
head.next = tail;
tail.prev = head;
tail.Name = "Tail";
tail.next = null;
count = 0;
}
public DoublyLinkedList()
{
head = new DoubleNode();
tail = new DoubleNode();
head.Name = "Head";
head.prev = null;
head.next = tail;
tail.prev = head;
tail.Name = "Tail";
tail.next = null;
count = 0;
}
public bool InsertAtHead(string n)
{
DoubleNode node = new DoubleNode();
node.Name = n;
node.next = head.next;
node.next.prev = node;
node.prev = head;
head.next = node;
count++;
return(true);
}
public bool InsertAtTail(string n)
{
DoubleNode node = new DoubleNode();
node.Name = n;
node.next = tail;
node.prev = tail.prev;
node.prev.next = node;
tail.prev = node;
count++;
return(true);
}
public void PrintFromHead()
{
if (head.next != null && head.next != tail)
{
DoubleNode cur = head.next;
Console.WriteLine(cur.Name);
while (cur.next != tail)
{
cur = cur.next;
Console.WriteLine(cur.Name);
}
cur = null;
}
}
public void PrintFromTail()
{
if (tail.prev != null && tail.prev != head)
{
DoubleNode cur = tail.prev;
Console.WriteLine(cur.Name);
while (cur.prev != head)
{
cur = cur.prev;
Console.WriteLine(cur.Name);
}
cur = null;
}
}
public bool Contains(T data)
{
DoubleNode <T> current = _head;
while (current != null)
{
if (current.Data.Equals(data))
{
return(true);
}
current = current.Next;
}
return(false);
}
public void Add(T data)
{
DoubleNode <T> node = new DoubleNode <T>(data);
if (_head == null)
{
_head = node;
}
else
{
_tail.Next = node;
node.Previous = _tail;
}
_tail = node;
_count++;
}
public void AddFirst(T data)
{
DoubleNode <T> node = new DoubleNode <T>(data);
DoubleNode <T> temp = _head;
node.Next = temp;
_head = node;
if (_count == 0)
{
_tail = _head;
}
else
{
temp.Previous = node;
}
_count++;
}
public bool RemoveNode(string n)
{
DoubleNode cur = head;
while (cur != tail)
{
if (cur.Name == n)
{
cur.prev.next = cur.next;
cur.next.prev = cur.prev;
cur = null;
count--;
return(true);
}
else
{
cur = cur.next;
}
}
cur = null;
return(false);
}
public bool InsertAtPosition(int pos, string n)
{
if (pos <= count)
{
DoubleNode cur = head;
DoubleNode newNode = new DoubleNode();
newNode.Name = n;
while (pos >= 0 && cur != tail)
{
cur = cur.next;
pos--;
}
newNode.next = cur;
newNode.prev = cur.prev;
cur.prev.next = newNode;
count++;
}
else
{
return false;
}
return true;
}
public bool InsertAtPosition(int pos, string n)
{
if (pos <= count)
{
DoubleNode cur = head;
DoubleNode newNode = new DoubleNode();
newNode.Name = n;
while (pos >= 0 && cur != tail)
{
cur = cur.next;
pos--;
}
newNode.next = cur;
newNode.prev = cur.prev;
cur.prev.next = newNode;
count++;
}
else
{
return(false);
}
return(true);
}
public bool Remove(T data)
{
DoubleNode <T> current = _head;
while (current != null)
{
if (current.Data.Equals(data))
{
break;
}
current = current.Next;
}
if (current != null)
{
if (current.Next != null)
{
current.Next.Previous = current.Previous;
}
else
{
_tail = current.Previous;
}
if (current.Previous != null)
{
current.Previous.Next = current.Next;
}
else
{
_head = current.Next;
}
_count--;
return(true);
}
return(false);
}
public bool InsertAfter(string ToFind, string n)
{
DoubleNode cur = head;
while (cur != tail)
{
if (cur.Name == ToFind)
{
DoubleNode newNode = new DoubleNode();
newNode.Name = n;
newNode.next = cur.next;
newNode.prev = cur;
cur.next = newNode;
count++;
return true;
}
else
{
cur = cur.next;
}
}
cur = null;
return false;
}
public bool InsertAfter(string ToFind, string n)
{
DoubleNode cur = head;
while (cur != tail)
{
if (cur.Name == ToFind)
{
DoubleNode newNode = new DoubleNode();
newNode.Name = n;
newNode.next = cur.next;
newNode.prev = cur;
cur.next = newNode;
count++;
return(true);
}
else
{
cur = cur.next;
}
}
cur = null;
return(false);
}
public bool InsertAtTail(string n)
{
DoubleNode node = new DoubleNode();
node.Name = n;
node.next = tail;
node.prev = tail.prev;
node.prev.next = node;
tail.prev = node;
count++;
return true;
}
public void Clear()
{
_head = null;
_tail = null;
_count = 0;
}