; maze printing:
(display "+")
(for-each (lambda (?) (display "--+")) (iota WIDTH))
(print)
(for-each (lambda (l)
            ; left wall (always)
            (display "|")
            ; draw right wall
            (for-each (lambda (x)
                        (display "  ")
                        (display (if (zero? (band x #b10)) " " "|")))
               l)
            (print)
            (display "+")
            ; draw bottom wall
            (for-each (lambda (x)
                        (display (if (zero? (band x #b01)) "  " "--"))
                        (display "+"))
               l)
            (print))
   maze)
(print)