/***************************************************************************
* Method: addafter
* Purpose:
* Insert a key in the position already found by tree_search.
* Return a pointer to the user's data in the tree. If the value
* pointer passed in is null, then we allocate the block, but don't
* initialise it to anything. */
public TreeItem addafter(TreeItem place, ulong key, object value )
{
if( place == null ){
first = new TreeItem( this, key, value );
return first;
}
TreeItem child = new TreeItem( this, key, value );
if( child.key < place.key ) place.left = child; /* should go on left leg */
else place.right = child;
return child;
}
/***************************************************************************
* Method: search
* Purpose:
* Find an element. If not, find it's correct parent item */
public TreeItem search(ulong key, out TreeItem place)
{
TreeItem item = getitem( key );
if( item == null ){
place = null; /* no items in tree. set placeholder to null to * indicate insert at top of tree */
return null; /* return null to indicate key not found */
}
if( item.key == key ){
place = null; /* found the key already there set pplace to null just for safety */
return item; /* give the user a pointer to his data */
}
place = item; /* key was not found - getitem has returned the parent - set this as the place for new insertions */
return null; /* return null to indicate that the key was not found */
}
public Tree()
{
first = null;
}
public TreeItem( Tree rootParam, ulong keyParam, object value )
{
root = rootParam;
key = keyParam;
left = null;
right = null;
data = value;
refCount = 0;
}
