// Support Methods
private void BalanceTree()
{
data.HeightCalc();
AVLElement e = data.BFSearch();
if (e == null)
{
return;
}
AVLElement l = (AVLElement)e.left;
AVLElement r = (AVLElement)e.right;
if (e.BalanceFactor() == -2)
{ // -- and - (single rotation)
if (l.BalanceFactor() == -1)
{
e.RightRotation();
}
// -- and + (double rotation)
else if (l.BalanceFactor() == 1)
{
l.LeftRotation();
e.RightRotation();
}
}
else if (e.BalanceFactor() == 2)
{ // ++ and + (single rotation)
if (r.BalanceFactor() == 1)
{
e.LeftRotation();
}
// ++ and - (double rotation)
else if (r.BalanceFactor() == -1)
{
r.RightRotation();
e.LeftRotation();
}
}
data.HeightCalc();
}
public bool Delete(int element)
{
// delete from class BinSearchTree
InfoReturn res = base.Delete(data, element);
if (res.success == false)
{
return(false);
}
data = (AVLElement)res.newRoot;
do
{
BalanceTree();
}while (data.BFSearch() != null);
return(true);
}