#!perl -l $a='-';$a.=$".$a,$"x=3for 1..pop;print$a
#!perl -l $_='-';$b=' ';for$a(1..pop){$_.=$b.$_;$b x=3}print
#!perl -l sub c{my($l,$b)=@_;$l<2?($b?'-':' '):c($l/=3,$b).c($l).c($l,$b)}print c(3**pop,1)