unit Unit1;

{$mode objfpc}{$H+}

interface

uses

  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls;

type

  { TForm1 }

  TForm1 = class(TForm)

    Label1: TLabel;

    procedure FormCreate(Sender: TObject);

    procedure FormMouseDown(Sender: TObject; Button: TMouseButton;

      Shift: TShiftState; X, Y: Integer);

    procedure FormPaint(Sender: TObject);

  private

    { private declarations }

  public

    { public declarations }

  end;

const

  cols = 10;

  rows = 10;

  size = 40;

var

  Form1: TForm1;

  walls: array [0..cols, 0..rows] of boolean;

  vizited: array [0..cols, 0..rows] of boolean;

  px, py: integer;

implementation

{$R *.lfm}

function Go(x, y, dx, dy: integer): boolean;

begin

  Result := false;

  if (x>=0) and (y>=0) and (x

    vizited[x, y] := true;

    px := x; py := y;

    Form1.Refresh;

    Application.ProcessMessages;

    Sleep(100);

    if (x=dx) and (y=dy) then begin

      Result := true;

    end else begin

      if Go(x-1, y, dx, dy) then Result := true else

      if Go(x, y-1, dx, dy) then Result := true else

      if Go(x+1, y, dx, dy) then Result := true else

      if Go(x, y+1, dx, dy) then Result := true;

    end;

    if not Result then begin

      px := x; py := y;

      Form1.Refresh;

      Application.ProcessMessages;

      Sleep(100);

    end;

  end;

end;

procedure TForm1.FormCreate(Sender: TObject);

var

  x, y: integer;

begin

  Randomize;

  for x := 0 to cols-1 do begin

    for y := 0 to rows-1 do begin

      if Random > 0.5 then begin

        walls[x, y] := true;

      end else begin

        walls[x, y] := false;

        px := x;

        py := y;

      end;

    end;

  end;

end;

procedure TForm1.FormPaint(Sender: TObject);

var

  x, y: integer;

begin

  for x := 0 to cols-1 do begin

    for y := 0 to rows-1 do begin

      if walls[x, y] then begin

        Canvas.Brush.Color := clBlack;

      end else begin

        Canvas.Brush.Color := clWhite;

      end;

      Canvas.FillRect(Rect(x*size, y*size, (x+1)*size, (y+1)*size));

    end;

  end;

  Canvas.Brush.Color := clRed;

  Canvas.Ellipse(px*size, py*size, (px+1)*size, (py+1)*size);

end;

procedure TForm1.FormMouseDown(Sender: TObject; Button: TMouseButton;

  Shift: TShiftState; X, Y: Integer);

var

  dx, dy, vx, vy: integer;

begin

  dx := x div size;

  dy := y div size;

  if (dx>=0) and (dy>=0) and (dx

    if Button = mbLeft then begin

      walls[dx, dy] := not walls[dx, dy];

      Refresh;

    end;

    if Button = mbRight then begin

      for vx := 0 to cols-1 do begin

        for vy := 0 to rows-1 do begin

          vizited[vx, vy] := false;

        end;

      end;

      if not Go(px, py, dx, dy) then ShowMessage('Path not found');

      Refresh;

    end;

  end;

end;

end.