paper 80
pen 0
command square a b c d
{
line a b c b
line c b c d
line c d a d
line a d a b
}
repeat a 0 50
{
square (2*a+5) (10*a) (2*2*a+5) (10*a+30)
square (a*a) (a*a+10) (a*10) (a*3)
square (a*a) (a*a/10) (a*a*2) a
}