public ComparableNode RemoveWithRunner(ComparableNode node)
{
var slow = node;
var fast = node;
while (slow != null)
{
var previous = slow;
while (fast != null)
{
if (slow.CompareTo(fast) == 0)
{
previous.Next = fast.Next;
}
else
{
previous = fast;
}
fast = fast.Next;
}
slow = slow.Next;
if (slow != null)
{
fast = fast.Next;
}
}
return(node);
}
public ComparableNode Remove(ComparableNode node)
{
var existingNodes = new Dictionary <int, bool>();
var head = node;
var previous = node;
while (node != null)
{
if (existingNodes.ContainsKey(node.Value))
{
previous.Next = node.Next;
}
else
{
existingNodes.Add(node.Value, true);
}
previous = node;
node = node.Next;
}
return(head);
}
public ComparableNode Partition(ComparableNode node, ComparableNode pivotNode)
{
if (node == null)
{
return(null);
}
ComparableNode leftBegin = null;
ComparableNode leftEnd = null;
ComparableNode rightBegin = null;
ComparableNode rightEnd = null;
while (node != null)
{
if (node.CompareTo(pivotNode) == 0)
{
if (leftBegin == null)
{
leftBegin = node;
leftEnd = leftBegin;
}
else
{
leftEnd.Next = node;
leftEnd = leftEnd.Next;
}
}
else
{
if (rightBegin == null)
{
rightBegin = node;
rightEnd = rightBegin;
}
else
{
rightEnd.Next = node;
rightEnd = rightEnd.Next;
}
}
node = node.Next;
}
if (leftEnd != null)
{
leftEnd.Next = null;
}
if (rightEnd != null)
{
rightEnd.Next = null;
}
if (leftBegin == null && rightBegin != null)
{
return(rightBegin);
}
if (rightBegin == null)
{
return(leftBegin);
}
leftEnd.Next = rightBegin;
return(leftBegin);
}