1 665c255d 2023-08-04 jrmu (element-of-set? x (adjoin-set x S))
 2 665c255d 2023-08-04 jrmu (element-of-set? x (union-set S T))
 3 665c255d 2023-08-04 jrmu (or (element-of-set? x S) (element-of-set? x T))
 4 665c255d 2023-08-04 jrmu (element-of-set? x '())
 5 665c255d 2023-08-04 jrmu (define (element-of-set? x set)
 6 665c255d 2023-08-04 jrmu   (cond ((null? set) false)
 7 665c255d 2023-08-04 jrmu 	((equal? x (car set)) true)
 8 665c255d 2023-08-04 jrmu 	(else (element-of-set? x (cdr set)))))
 9 665c255d 2023-08-04 jrmu (define (adjoin-set x set)
10 665c255d 2023-08-04 jrmu   (if (element-of-set? x set)
11 665c255d 2023-08-04 jrmu       set
12 665c255d 2023-08-04 jrmu       (cons x set)))
13 665c255d 2023-08-04 jrmu (define (intersection-set set1 set2)
14 665c255d 2023-08-04 jrmu   (cond ((or (null? set1) (null? set2)) '())
15 665c255d 2023-08-04 jrmu 	((element-of-set? (car set1) set2)
16 665c255d 2023-08-04 jrmu 	 (cons (car set1)
17 665c255d 2023-08-04 jrmu 	       (intersection-set (cdr set1) set2)))
18 665c255d 2023-08-04 jrmu 	(else (intersection-set (cdr set1) set2))))
19 665c255d 2023-08-04 jrmu 
20 665c255d 2023-08-04 jrmu (define (union-set