/// <summary>
/// Split treap on two treaps.All items right > item, item > all items left.
/// </summary>
/// <param name="item"></param>
/// <param name="left"></param>
/// <param name="right"></param>
internal void Split(int item, out Treap left, out Treap right)
{
left = null;
right = null;
Treap newTree = null;
if (this.Item <= item)
{
if (this.Right == null)
{
right = null;
}
else
{
this.Right.Split(item, out newTree, out right);
}
left = new Treap(this.Item, this.Priority, this.Left, newTree);
}
else
{
if (this.Left == null)
{
left = null;
}
else
{
this.Left.Split(item, out left, out newTree);
}
right = new Treap(this.Item, this.Priority, newTree, this.Right);
}
}
private Treap(int item, int priority, Treap left, Treap right)
{
this.Item = item;
this.Priority = priority;
this.Left = left;
this.Right = right;
}
private Treap(int item, int priority, Treap left, Treap right)
{
this.Item = item;
this.Priority = priority;
this.Left = left;
this.Right = right;
}
private void InitializeList(Treap treap)
{
if (treap == null || (treap.Item == 0 && treap.Priority == 0))
{
return;
}
InitializeList(treap.Left);
this.list.Add(treap.Item);
InitializeList(treap.Right);
}
private void InitializeList(Treap treap)
{
if (treap == null || (treap.Item == 0 && treap.Priority == 0))
{
return;
}
InitializeList(treap.Left);
this.list.Add(treap.Item);
InitializeList(treap.Right);
}
internal void Remove(int item)
{
Treap left = new Treap();
Treap right = new Treap();
Treap removeItem = new Treap();
this.Split(item - 1, out left, out right);
this.Split(item, out removeItem, out right);
Treap result = Merge(left, right);
this.Item = result.Item;
this.Priority = result.Priority;
this.Left = result.Left;
this.Right = result.Right;
}
internal void Add(int item)
{
if (this.Find(item))
{
return;
}
Treap left;
Treap right;
this.Split(item, out left, out right);
Treap result = new Treap(item, random.Next());
result = Merge(left, result);
result = Merge(result, right);
this.Item = result.Item;
this.Priority = result.Priority;
this.Left = result.Left;
this.Right = result.Right;
}
/// <summary>
/// Merge two treaps. All items right > all items left!!!
/// </summary>
/// <param name="left"></param>
/// <param name="right"></param>
/// <returns></returns>
internal static Treap Merge(Treap left, Treap right)
{
if (left == null)
{
return(right);
}
if (right == null)
{
return(left);
}
if (left.Priority > right.Priority)
{
Treap newRight = Merge(left.Right, right);
return(new Treap(left.Item, left.Priority, left.Left, newRight));
}
else
{
Treap newLeft = Merge(left, right.Left);
return(new Treap(right.Item, right.Priority, newLeft, right.Right));
}
}
/// <summary>
/// Merge two treaps. All items right > all items left!!!
/// </summary>
/// <param name="left"></param>
/// <param name="right"></param>
/// <returns></returns>
internal static Treap Merge(Treap left, Treap right)
{
if (left == null)
{
return right;
}
if (right == null)
{
return left;
}
if (left.Priority > right.Priority)
{
Treap newRight = Merge(left.Right, right);
return new Treap(left.Item, left.Priority, left.Left, newRight);
}
else
{
Treap newLeft = Merge(left, right.Left);
return new Treap(right.Item, right.Priority, newLeft, right.Right);
}
}
internal TreapIterator(Treap treap)
{
InitializeList(treap);
}
internal TreapIterator(Treap treap)
{
InitializeList(treap);
}
/// <summary>
/// Split treap on two treaps.All items right > item, item > all items left.
/// </summary>
/// <param name="item"></param>
/// <param name="left"></param>
/// <param name="right"></param>
internal void Split(int item, out Treap left, out Treap right)
{
left = null;
right = null;
Treap newTree = null;
if (this.Item <= item)
{
if (this.Right == null)
{
right = null;
}
else
{
this.Right.Split(item, out newTree, out right);
}
left = new Treap(this.Item, this.Priority, this.Left, newTree);
}
else
{
if (this.Left == null)
{
left = null;
}
else
{
this.Left.Split(item, out left, out newTree);
}
right = new Treap(this.Item, this.Priority, newTree, this.Right);
}
}
internal void Remove(int item)
{
Treap left = new Treap();
Treap right = new Treap();
Treap removeItem = new Treap();
this.Split(item - 1, out left, out right);
this.Split(item, out removeItem, out right);
Treap result = Merge(left, right);
this.Item = result.Item;
this.Priority = result.Priority;
this.Left = result.Left;
this.Right = result.Right;
}
internal void Add(int item)
{
if (this.Find(item))
{
return;
}
Treap left;
Treap right;
this.Split(item, out left, out right);
Treap result = new Treap(item, random.Next());
result = Merge(left, result);
result = Merge(result, right);
this.Item = result.Item;
this.Priority = result.Priority;
this.Left = result.Left;
this.Right = result.Right;
}
public void Initialize()
{
treap = new Treap();
}
