program teglalapok_veletlenul;
uses graph, crt;
var gd,gm,x1,y1,x2,y2,szin:integer;
    i,j:shortint;
    c:char;
begin
     detectgraph(gd,gm);
     initgraph(gd,gm,'c:\tp\bgi');
     repeat
      setlinestyle(random(4),0,random(4));
      szin:=random(16);
      setcolor(szin);
      setfillstyle(random(16),random(16));
      x1:=random(640);
      y1:=random(480);
      x2:=random(640);
      y2:=random(480);
      rectangle(x1,y1,x2,y2);
      if x1>x2 then i:=-1 else i:=1;
      if y1>y2 then j:=-1 else j:=1;
      bar(x1+i,y1+j,x2-i,y2-j);
     until keypressed;
     readkey;
     readln;
     closegraph;
end.