(setq a(make-array'(80 80))d 1 x 40 y x o x b x r x l x)(#1=dotimes(i(read)(#1#'(- b o -1)(#1#`(- r l -1)(princ(if(aref a(+ .'o)(+ .`l))"#"" ")))(terpri)))(setf x(+(rem(- d 2)2)x)y(+(rem(1- d)2)y)d(mod(+(if #2=(aref a y x)1 -1)d)4)#2#(not #2#)o(min o y)b(max b y)r(max r x)l(min l x)))
Note that non-ascii characters in the above source code will be escaped (such as \x9f).