sicp-solutions/chapter-2/ex-2.62.scm

11 lines
342 B
Scheme

#lang sicp
(define (union-set set1 set2)
(cond ((null? set1) set2)
((null? set2) set1)
((< (car set1) (car set2)) (cons (car set1)
(union-set (cdr set1) set2)))
((= (car set1) (car set2)) (cons (car set1)
(union-set (cdr set1) (cdr set2))))
((> (car set1) (car set2)) (cons (car set2)
(union-set set1 (cdr set2))))))