Ausbalancierte Bäume Sortieren mit AVL-Bäumen

{ Datentypen und Strings. }
var By1 : Byte absolute Key1;
By2 : Byte absolute Key2;
In1 : Integer absolute Key1;
In2 : Integer absolute Key2;
Rl1 : Real absolute Key1;
Rl2 : Real absolute Key2;
St1 : String absolute Key1;
St2 : String absolute Key2;
begin
case KeyType of
KChar, KByte : if By1By2 then
Compare:=Bigger
else Compare:=Equal;
KInteger : if In1In2 then
Compare:=Bigger
else Compare:=Equal;
KReal : if Rl1Rl2 then
Compare:=Bigger
else Compare:=Equal;
KString : if St1St2 then
Compare:=Bigger
else Compare:=Equal;
end;
end;
{* ════════════════════════════════════════════*}
function Height(HTree: AvlTree): Integer;
var H1,H2 : Integer;
begin
if HTree=NIL then
begin
Height:=0;
Exit;
end;
H1:=Height(HTree^.Left);
H2:=Height(HTree^.Right);
if H1>H2 then Height:=Succ(H1)
else Height:=Succ(H2);
end;
{* ════════════════════════════════════════════*}
function Lowest(Var LData;
BegTree: AvlTree): AvlTree;
begin
if BegTree=nil then
begin
Lowest:=nil;
Exit;
end;
while BegTree^.Leftnil do
BegTree:=BegTree^.Left;