public void ReverseInPlace(ref SNode node, int k)
{
var headToResult = new SNode();
var prev = headToResult;
var visitor = node;
while (visitor != null)
{
var head = visitor;
int i = 0;
while (i < k - 1 && visitor != null)
{
visitor = visitor.Next;
i++;
}
var tail = visitor;
if (visitor != null)
{
visitor = visitor.Next;
tail.Next = null;
}
head = new ReverseSingleLinkedList().Reverse(head);
prev.Next = head;
prev = FindTail(head);
}
node = headToResult.Next;
}
public SNode Zip(SNode list)
{
var fast = list;
var slow = list;
while (slow != null && fast != null && fast.Next != null)
{
slow = slow.Next;
fast = fast.Next.Next;
}
var head1 = list;
var head2 = slow.Next;
slow.Next = null; // split lists
head2 = new ReverseSingleLinkedList().Reverse(head2);
// Merge head1 and head2
var it1 = head1;
var it2 = head2;
bool useLeft = true;
SNode result = new SNode();
SNode tail = new SNode();
while (it1 != null && it2 != null)
{
var nodeToAdd = useLeft ? new SNode(it1.Value) : new SNode(it2.Value);
if (result.Next == null)
{
result.Next = nodeToAdd;
tail.Next = result.Next;
}
else
{
AddToTail(ref tail, nodeToAdd);
}
if (useLeft)
{
it1 = it1.Next;
}
else
{
it2 = it2.Next;
}
useLeft = !useLeft;
}
AddRemainingItems(ref tail, it1);
AddRemainingItems(ref tail, it2);
return(result.Next);
}
public void Reverse(ref SNode node, int k)
{
var splitLists = new List <SNode>();
var nodeCount = CountNodes(node);
int finalListCount = (int)Math.Ceiling((decimal)nodeCount / k);
int i = 0;
SNode nextList = node;
while (i < finalListCount)
{
SNode head = nextList;
SNode it = head;
int m = 0;
while (m < k - 1 && it != null)
{
it = it.Next;
m++;
}
if (it != null)
{
nextList = it.Next;
it.Next = null;
}
splitLists.Add(head);
i++;
}
var reversedLists = new List <SNode>();
foreach (var list in splitLists)
{
var rlist = new ReverseSingleLinkedList().Reverse(list);
reversedLists.Add(rlist);
}
node = Merge(reversedLists);
}
