(defun remove (elem array)
	(cond
		((null array) nil)
		((eql elem (car array)) (cdr array))
		(t (cons (car array) (remove elem (cdr array))))
	)
)

(defun in (elem array)
	(cond
		((null array) nil)
		((eql elem (car array)) t)
		(t (in elem (cdr array)))
	)
)

(defun set (array)
	(cond
		((null array) nil)
		((in (car array) (cdr array)) (set (cdr array)))
		(t (cons (car array) (set (cdr array))))
	)
)

(defun РАВЕНСТВО-МНОЖЕСТВ (set1 set2)
	(cond
		((and (null set1) (null set2)) t)
		((null set1) nil)
		((null set2) nil)
		((in (car set1) set2) (РАВЕНСТВО-МНОЖЕСТВ (cdr set1) (remove (car set1) set2)))
		(t nil)
	)
)

(print (РАВЕНСТВО-МНОЖЕСТВ '(1 2 3 4) '(4 1 3 2)))