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type
  TData = record
    MCarBrand: string[25];           
    MModelOfCar: string[20];        
  end;
 
  PTBase = ^TBase;                   
 
  TBase = record
    MData: Tdata;
    next: PTBase                  
  end;
 
var
  head: PTBase;                    
  f: file of PTBase;               
{------------------------------------------------------------------------------}
procedure TForm1.BitBtn1Click(Sender: TObject);
var
 
  node: PTBase;   
  curr: PTBase;   
  pre: PTBase;     
begin
  new(node); 
 
  node^.MData.MCarBrand := Edit1.Text;               
  node^.MData.MModelOfCar := Edit2.Text;             
 
  curr := head;
  pre := NIL;
 
  while (curr <> NIL) and (node^.MData.MCarBrand > curr^.MData.MCarBrand) do
    begin
      pre := curr;
      curr := curr^.next
    end;
 
  if pre = NIL
    then
      begin
        node^.next := head;
        head := node
      end
    else
      begin
        node^.next := pre^.next;
        pre^.next := node
      end;
 
  Edit1.text := '';
  Edit2.text := '';
 
  Edit1.SetFocus;
 
  AssignFile(f, 'C:\111.db');
  Reset(f);
  Seek(f, 0);
  curr := head;
  while curr <> NIL do
    begin
     Write(f, curr^.MData);
      curr := curr^.next
    end;
  CloseFile(f);
  dispose(node)
end;
{------------------------------------------------------------------------------}
procedure TForm1.BitBtn2Click(Sender: TObject);
var
  curr: PTBase;
  n: integer;  
  st: string;   
begin
  n := 0;
  st := '';
  AssignFile(f, 'C:\111.db');
  Reset(f);
  Seek(f, 0);
  new(curr);
  while not EOF(F) do
    begin
      read(f, curr^.Mdata);
      with curr^ do
        begin
          n := n + 1;
          st := st + MData.MCarBrand + ' ' + MData.MModelOfCar + ' ' + #13;
        end;
      curr := curr^.next; 
    end;
  CloseFile(f);
  if n <> 0
    then ShowMessage('Список:' + #13 + st)
  else ShowMessage('В списке нет элементов.')
 
end;
{------------------------------------------------------------------------------}
end.

AssignFile(f, 'C:\111.db');
  Reset(f);                   // замени на ReWrite() или Append()
  Seek(f, 0);
  curr := head;
  while curr <> NIL do
    begin
     Write(f, curr^.MData);
      curr := curr^.next
    end;
  CloseFile(f);

f: file of TData;