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/* Implementation for Objective-C SplayTree collection object
Copyright (C) 1993,1994 Free Software Foundation, Inc.
Written by: R. Andrew McCallum <mccallum@gnu.ai.mit.edu>
Date: May 1993
This file is part of the GNU Objective C Class Library.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <objects/SplayTree.h>
#include <objects/IndexedCollectionPrivate.h>
@implementation SplayTree
+ initialize
{
if (self == [SplayTree class])
[self setVersion:0]; /* beta release */
return self;
}
/* Make this a function ? */
- _doSplayOperationOnNode: aNode
{
id parent = [aNode parentNode];
id parentRightChild =
((parent == [self nilNode]) ? [self nilNode] : [parent rightNode]);
if (aNode == _contents_root || aNode == [self nilNode])
{
return self;
}
else if (aNode == parentRightChild)
{
if (parent == _contents_root)
{
[self leftRotateAroundNode:parent];
}
else if (NODE_IS_RIGHTCHILD(parent))
{
[self leftRotateAroundNode:[parent parentNode]];
[self leftRotateAroundNode:parent];
}
else
/* NODE_IS_LEFTCHILD(parent) */
{
[self leftRotateAroundNode:parent];
[self rightRotateAroundNode:[aNode parentNode]];
}
}
else
/* aNode == parentLeftChild */
{
if (parent == _contents_root)
{
[self rightRotateAroundNode:parent];
}
else if (NODE_IS_LEFTCHILD(parent))
{
[self rightRotateAroundNode:[parent parentNode]];
[self rightRotateAroundNode:parent];
}
else
/* NODE_IS_RIGHTCHILD(parent) */
{
[self rightRotateAroundNode:parent];
[self leftRotateAroundNode:[aNode parentNode]];
}
}
return self;
}
- splayNode: aNode
{
while (aNode != _contents_root)
[self _doSplayOperationOnNode:aNode];
return self;
}
/* We could make this a little more efficient by doing the splay as
we search down the tree for the correct insertion point. */
- sortAddElement: (elt)newElement byCalling: (int(*)(elt,elt))aFunc
{
[super sortAddElement:newElement byCalling:aFunc];
[self splayNode:newElement.id_u];
return self;
}
- insertElement: (elt)newElement before: (elt)oldElement
{
[super insertElement:newElement before:oldElement];
// ?? [self splayNode:newElement.id_u];
return self;
}
- insertElement: (elt)newElement after: (elt)oldElement
{
[super insertElement:newElement after:oldElement];
// ?? [self splayNode:newElement.id_u];
return self;
}
- insertElement: (elt)newElement atIndex: (unsigned)index
{
[super insertElement:newElement atIndex:index];
// ?? [self splayNode:newElement.id_u];
return self;
}
- (elt) removeElement: (elt)anElement
{
id parent = [anElement.id_u parentNode];
[super removeElement:anElement];
if (parent && parent != [self nilNode])
[self splayNode:parent];
return anElement;
}
@end
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.