(defun gray (a b c d)
	(setf res ())
	(if (= a 1)
	  	(setf res (append res '(1)))
	  	(setf res (append res '(0))))
	(if (or (and (eq a 0) (eq b 1)) (and (eq a 1) (eq b 0)))
	  	(setf res (append res '(1)))
	  	(setf res (append res '(0))))
	(if (or (and (eq b 0) (eq c 1)) (and (eq b 1) (eq c 0)))
	  	(setf res (append res '(1)))
	  	(setf res (append res '(0))))
	(if (or (and (eq c 0) (eq d 1)) (and (eq c 1) (eq d 0)))
	  	(setf res (append res '(1)))
	  	(setf res (append res '(0))))
	(mapcar (lambda (x) (format t "~A" x)) res)
)

(setf a (read))
(gray (mod (/ a 1000) 10) (mod (/ a 100) 10) (mod (/ a 10) 10) (mod a 10) )