Program Classificator;
Type  T = string;
      The_Data = record    {Dannie v liste}
       s: t;
      end;

      PItem = ^TItem;   {element dereva}
      TItem = record
       Data : The_data;
       {klu4 dlya pechati }
       Key : integer;
       Next : PItem; {ykazatel na brata}
       Children : PItem; {ykazatel na sinovei}
      end;

function FindByKey (root: PItem; k:integer):PItem;
{ykazatel na roditelya po ego indeksy}
  var p, found :PItem;
  begin
    found:= nil;
    p:=root;
     {esli koren nenylevoi}
     If p <> nil then
      begin
       while (found = nil) and (p <> nil)  do
        begin
         {esli klu4 kornevogo elementa raven iskomumu, prekrawaem poisk}
         if p^.key = k then found:=p
         else found := FindByKey(p^.children,k); {recursivno ishem v detyah}

         p:= p^.next;
        end;
      end;
      {vozvrashaem resultat, nil = esli ne nashli}
      findBykey:= found;
    end;

{Peredaem v proceduru koren dereva, ykazatel na roditelya i vnosimie dannie}
procedure Add ( var root:PItem;parent:PItem; value:the_data);
var new_item,p_child:PItem;
 begin
  {videlyem pamyt i obnulyaem spisok optomkov i bratev}
  new(new_item);
  new_item^.next:=nil; new_item^.children:=nil;
  new_item^.key:= 0;
  new_item^.data:= value; {kopiruem dannie v pamyt}
  If parent = nil then {derevo nulevoe}
   begin
   {ne kopiruutsya li dannie}
    if root <> nil  then
     begin writeln ('ERROR - duplicate data!') ; dispose(new_item) ;
     end
     else root := new_Item; {vse ok}
     end
     else begin
     {i 2 slu4ai kogda roditel naiden, dobavlyem k potomkam}
     p_child:=parent^.children;
      if p_child = nil then parent^.children:=new_item
       else begin {a  esli yge est bratya}
        while p_child^.next <> nil do p_child:=p_child^.next;
        p_child^.next:= new_item;
       end;
      end;
     end;

var curr_index: integer;

procedure Printing(level: integer; root: PItem;
          visual: boolean);
var p: PItem;
begin
  p := root;
  while p <> nil do begin
    inc(curr_index); p^.key := curr_index;

    if visual then
      writeln(p^.key:4, '':succ(2*level), p^.data.s);

    Printing(level+1, p^.children, visual);

    p := p^.next;
  end;
end;

procedure Print(root: PItem; visual: boolean);
begin
  curr_index := 0;
  printing(0, root, visual);
end;

var
  i, p_ix: integer;
  r: the_data;
  tree_root, new_root: PItem;
  f: text;

begin
  tree_root := nil;
  for i := 1 to 3 do begin
    write('parent index = '); readln(p_ix);
    write('data = '); readln(r.s);

    Add(tree_root, FindByKey(tree_root, p_ix), r);

    Print(tree_root, true);
  end;
  Writeln ('Konec') ;
  readln;
  end.