type
  TFirst = object
  protected
    a: integer;
    procedure Draw; virtual;
  public
    procedure Show;
    constructor Create(ia: integer);
  end;
  TSecond1 = object(TFirst)
  protected
    b: integer;
    procedure Draw; virtual;
  public
    constructor Create(ia,ib: integer);
  end;
  TSecond2 = object(TFirst)
  protected
    s: string;
    procedure Draw; virtual;
  public
    constructor Create(ia: integer;ist:string);
  end;

constructor TFirst.Create(ia: integer);
begin
  a := ia;
end;

procedure TFirst.Show;
begin
  Draw;
  writeln;
end;

procedure TFirst.Draw;
begin
  writeln('a = ',a);
end;

constructor TSecond1.Create(ia,ib: integer);
begin
  inherited Create(ia);
  b := ib;
end;

procedure TSecond1.Draw;
begin
  writeln('a = ',a);
  writeln('b = ',b);
end;

constructor TSecond2.Create(ia: integer;ist: string);
begin
  inherited Create(ia);
  s := ist;
end;

procedure TSecond2.Draw;
begin
  writeln('a = ',a);
  writeln('s = ',s);
end;


var
  a: array [1..2] of ^TFirst;
  p1: ^TSecond1;
  p2: ^TSecond2;
  i: integer;

begin
  New(p1);
  p1^.Create(5,7);
  a[1] := p1;
  New(p2);  p2^.Create(9,'mama');
  p2^.Create(9,'mama');
  a[2] := p2;
  writeln('SizeOf(p1^)  = ',SizeOf(p1^));
  writeln('SizeOf(a[1]^) = ',SizeOf(a[1]^));
  writeln('SizeOf(p2^)  = ',SizeOf(p2^));
  writeln('SizeOf(a[2]^) = ',SizeOf(a[2]^));
  for i := 1 to 2 do
    a[i]^.Show;

  for i := 1 to 2 do
    dispose(a[i]);
  readln;
end.

type
  ptbase = ^tbase;
  tbase = object
    constructor create;
    procedure draw; virtual;
  end;

  ptfirst = ^tfirst;
  tfirst = object(tbase)
    value : integer;
    constructor create(i : integer);
    procedure draw; virtual;
  end;

  ptsecond = ^tsecond;
  tsecond = object(tbase)
    value : string;
    constructor create(s : string);
    procedure draw; virtual;
  end;

constructor tbase.create;
begin end;
procedure tbase.draw;
begin end;

constructor tfirst.create(i : integer);
begin
  inherited create;
  value := i;
end;
procedure tfirst.draw;
begin writeln(value); end;

constructor tsecond.create(s : string);
begin
  inherited create;
  value := s;
end;
procedure tsecond.draw;
begin writeln(value); end;

procedure draw_me(var obj : tbase);
begin
  obj.draw;
end;

var
  arr : array[1 .. 2] of ptbase;
  i : integer;
begin
  arr[1] := new(ptfirst, create(10));
  arr[2] := new(ptsecond, create('test'));
  for i := 1 to 2 do
  begin
    draw_me(arr[ i ]^)
  end;
  // удалять не забывай, чтоб потом когда функционал добавишь - утечек не было
end.

uses
  UBase, ULine, UCircle, Graph;

const
  n = 3;

var
  arr: array[1..n] of PTBase;
  i : integer;
  gd, gm: integer;
begin
  gd := Detect;
  InitGraph(gd,gm,'');
  arr[1] := new(PTLine, Create('Line1.txt',0,0,0,0,0,0,0));
  arr[2] := new(PTLine, Create('',9,3,3,100,500,800,100));
  arr[3] := new(PTCircle, Create('Circle1.txt',0,0,0,0,0,0));
  for i := 1 to n do
    arr[i]^.Show;


  readln;
  for i := 1 to n do
    arr[i]^.Destroy;
  CloseGraph;
end.

unit UBase;

interface

type
  PTBase = ^TBase;
  TBase = object
  protected
    Color: byte;
    procedure Draw(action: byte); virtual;
    procedure LoadFromFile(var f: text); virtual;
  public
    procedure Show;
    procedure Hide;
    constructor Create(FileName: string; iColor:byte);
    destructor Destroy;
  end;

implementation

uses
  Graph;

constructor TBase.Create(FileName: string; iColor:byte);
var
  f: text;
begin
  if FileName = '' then
    Color := iColor
  else
  begin
    assign(f,FileName);
    reset(f);
    LoadFromFile(f);
    close(f);
  end;
end;

procedure TBase.LoadFromFile(var f: text);
begin
  readln(f,Color);
end;

procedure TBase.Draw(action: byte);
begin
  if action = 1 then
    SetColor(Color)
  else
    SetColor(GetBKColor);
end;


procedure TBase.Show;
begin
  Draw(1);
end;

procedure TBase.Hide;
begin
  Draw(0);
end;

destructor TBase.Destroy;
begin
  Hide;
end;



end.

unit UCircle;

interface

uses
  UBase;

type
  TPoint = record
    x, y: integer;
  end;

  PTCircle = ^TCircle;
  TCircle = object(TBase)
  protected
    pb: TPoint;
    Radius: integer;
    LineType, LineWidth: word;
    procedure Draw(action: byte); virtual;
    procedure LoadFromFile(var f: text); virtual;
  public
    constructor Create(FileName: string; iColor:byte;
      iLineType, iLineWidth: word; x1, y1, iRadius: integer);
    destructor Destroy;
  end;

implementation

uses
  Graph;

constructor TCircle.Create(FileName: string; iColor:byte;
      iLineType, iLineWidth: word; x1, y1, iRadius: integer);
begin
  inherited Create(FileName, iColor);
  if FileName = '' then
  begin
    LineType := iLineType;
    LineType := iLineType;
    pb.x := x1;
    pb.y := y1;
    Radius := iRadius;
  end;
end;


procedure TCircle.LoadFromFile(var f: text);
begin
  inherited;
  readln(f,LineType,LineWidth);
  readln(f,pb.x,pb.y);
  readln(f,Radius);
end;

procedure TCircle.Draw(action: byte);
begin
  inherited;
  SetLineStyle(LineType,0,LineWidth);
  Circle(pb.x,pb.y,Radius);
end;

destructor TCircle.Destroy;
begin
  inherited;
end;



end.

unit ULine;

interface

uses
  UBase;

type
  TPoint = record
    x, y: integer;
  end;

  PTLine = ^TLine;
  TLine = object(TBase)
  protected
    pb, pe: TPoint;
    LineType, LineWidth: word;
    procedure Draw(action: byte); virtual;
    procedure LoadFromFile(var f: text); virtual;
  public
    constructor Create(FileName: string; iColor:byte;
      iLineType, iLineWidth: word; x1, y1, x2, y2: integer);
    destructor Destroy;
  end;

implementation

uses
  Graph;

constructor TLine.Create(FileName: string; iColor:byte;
      iLineType, iLineWidth: word; x1, y1, x2, y2: integer);
begin
  inherited Create(FileName, iColor);
  if FileName = '' then
  begin
    LineType := iLineType;
    LineType := iLineType;
    pb.x := x1;
    pb.y := y1;
    pe.x := x2;
    pe.y := y2;
  end;
end;

procedure TLine.LoadFromFile(var f: text);
begin
  inherited;
  readln(f,LineType,LineWidth);
  readln(f,pb.x,pb.y);
  readln(f,pe.x,pe.y);
end;

procedure TLine.Draw(action: byte);
begin
  inherited;
  SetLineStyle(LineType,0,LineWidth);
  Line(pb.x,pb.y,pe.x,pe.y);
end;

destructor TLine.Destroy;
begin
  inherited;
end;



end.