Uses Graph;

Const
  amount = 10;

(* Draws the gistogram of the given sequence on the screen *)
Procedure DrawGistogram(place: Integer;
          arr: Array of Integer; Color: Integer);
  Var
    i, size_x, Top: Integer;
    left, right: integer;
    start, range:
      Record
        x, y: Integer;
      End;
    s: string;

    numGeneral: integer;
  Begin
    Start.X := 1;
    Start.Y := GetMaxY;

    SetColor(White);
    SetBkColor(Black);
    Range.X := GetMaxX div 2;
    Range.Y := GetMaxY div 2;

    numGeneral := 0;
    for i := 0 to pred(amount) do
      inc(numGeneral, arr[i]);

    Line(Start.X, Start.Y, Start.X, Start.Y);

    size_x := Range.X div amount;
    SetFillStyle(SolidFill, Color);
    For i := 0 To Pred(amount) Do
      Begin
        left := Start.X + i * size_x;
        right := left + size_x;
        top := Start.Y - Trunc( Range.Y * arr[i] / NumGeneral );
        bar3d(left + 1, top + 1, right - 1, Start.Y - 1, 15, true);

        str(arr[i], s);
        outtextxy( left, Start.Y + 3, s );
      End;
  End;

const
  data: array[1 .. amount] of integer =
    (10, 12, 15, 20, 32, 55, 40, 32, 56, 12);

var
  grDriver: Integer;
  grMode: Integer;
  ErrCode: Integer;
begin
  grDriver := Detect;
  InitGraph(grDriver, grMode,'');
  ErrCode := GraphResult;
  if ErrCode <> grOk then
    begin
      writeln('error: ', grapherrormsg(errcode));
      readln; halt(100)
    end;

  DrawGistogram(0, data, Red);

  readln;
  closegraph;
end.