program ri;
uses graph, crt;
var d,m,viga,x,y: integer;
begin
d:= detect;
InitGraph(d, m, '');
viga:=GraphResult;
if viga<>GrOk then
writeln('Graafikaviga',GraphErrorMsg(viga))
else
begin
x:=GetMaxX div 4;
y:=GetMaxy div 4;
rectangle(x, y, 3*x, 3*y);
SetViewPort(x+1, y+1, 3*x-1, 3*y-1,clipon);
repeat
setcolor(succ(random(white)));
setlinestyle(0,0,1);
x:=random(GetMaxX);
y:=random(GetMaxY);
circle(x, y, random(GetMaxY div 4));
until keypressed;
CloseGraph;
end;
end.