(in-package :cs325-user)

(defun mt (lst1 lst2)
  (valid (mapcar 'mi lst1 lst2)))

(defun mi (x y)
  (and (or (eql x y) (var-p x)) (list x y)))

(defun valid (bdgs)
  (and (every (lambda (bdg) bdg) bdgs)
       bdgs))

;;; don't worry about how this works
(defun var-p (x)
  (and (symbolp x) (eql (char (symbol-name x) 0) #\?)))

(defun show-mt (lst1 lst2)
  (format t "~%~S ~S => ~S" lst1 lst2 (mt lst1 lst2)))

(defun test-mt ()
  (show-mt '(a b c) '(a b c))
  (show-mt '(a b c) '(a b b))
  (show-mt '(?x b c) '(a b c))
  (show-mt '(?x ?y ?z) '(a b c))
  (show-mt '(?x b ?x) '(a b c))
  )