public SingleLinkedListNode <T> Reverse(SingleLinkedListNode <T> p)
{
if (_head == null || _head.Next == null)
{
return(_head);
}
var head = new SingleLinkedListNode <T>(_head.Data);
head.Next = p;
var cur = p.Next;
p.Next = null;
SingleLinkedListNode <T> next = default;
while (cur != null)
{
//把tmlHead恒定的插入到到第二个结点
next = cur.Next;
cur.Next = head.Next;
head.Next = cur;
cur = next;
}
//把头结点放到尾部
var hnext = head.Next;
head.Next = null;
head = hnext;
return(head);
}
public void Remove(SingleLinkedListNode <T> node)
{
if (node == null || _head == null)
{
return;
}
//删除的是否为头结点
if (node == _head)
{
_head = node.Next;
return;
}
//找到node的上一个以及node的下一个
var tempNode = _head;
while (_head != null && tempNode.Next != node)
{
tempNode = tempNode.Next;
}
if (tempNode == null)
{
return;
}
tempNode.Next = tempNode.Next.Next;
}
public SingleLinkedListNode <T> MergeSortedList(SingleLinkedListNode <T> a, SingleLinkedListNode <T> b)
{
if (a == null)
{
return(b);
}
if (b == null)
{
return(a);
}
if (comparer == null)
{
throw new InvalidOperationException("must be provide IComparer");
}
var p = a;
var q = b;
SingleLinkedListNode <T> mergeNode;
//比较头，来确定新合并之后的头结点
if (comparer.Compare(p.Data, q.Data) < 0)
{
mergeNode = p;
p = p.Next;
}
else
{
mergeNode = q;
q = q.Next;
}
SingleLinkedListNode <T> r = mergeNode;
while (p != null && q != null)
{
if (comparer.Compare(p.Data, q.Data) < 0)
{
r.Next = p;
p = p.Next;
}
else
{
r.Next = q;
q = q.Next;
}
r = r.Next;
}
if (p != null)
{
r.Next = p;
}
else
{
r.Next = q;
}
return(mergeNode);
}
public void InsertToHead(SingleLinkedListNode <T> newNode)
{
if (_head == null)
{
InsertNodeToEmptyList(newNode);
}
else
{
_head.Next = newNode.Next;
newNode.Next = _head;
_head = newNode;
}
}
public void InsertToTail(SingleLinkedListNode <T> newNode)
{
var node = _head;
var tempNode = _head;
while (tempNode.Next != null)
{
tempNode = tempNode.Next;
}
newNode.Next = tempNode.Next;
tempNode.Next = newNode;
++_count;
}
public void InsertToTail(T item)
{
var newNode = new SingleLinkedListNode <T>(item);
if (_head == null)
{
InsertNodeToEmptyList(newNode);
}
else
{
InsertToTail(newNode);
}
}
public void AddAfter(SingleLinkedListNode <T> node, T item)
{
var newNode = new SingleLinkedListNode <T>(item);
if (_head == null)
{
InsertNodeToEmptyList(newNode);
}
else
{
newNode.Next = node.Next;
node.Next = newNode;
++_count;
}
}
//用快慢指针，遍历同一个节点，如果快慢指针相等，则说明有环
public bool HasCycle(SingleLinkedListNode <T> head)
{
if (head == null)
{
return(false);
}
SingleLinkedListNode <T> fast = head.Next.Next;
SingleLinkedListNode <T> slow = head.Next;
while (fast != null && fast.Next != null)
{
fast = fast.Next.Next;
slow = slow.Next;
if (slow == fast)
{
return(true);
}
}
return(false);
}
public void AddBefore(SingleLinkedListNode <T> node, T item)
{
}
public void InsertToHead(T item)
{
var node = new SingleLinkedListNode <T>(item);
InsertToHead(node);
}
private void InsertNodeToEmptyList(SingleLinkedListNode <T> newNode)
{
_head = newNode;
_count++;
}
