scip练习题2.20

scip练习2.20

(define (same-parity x . z)  (define (q? y) (= (remainder y 2) 1))  (define (o? y) (= (remainder y 2) 0))  (define (jg z f)     (define m '())     (define (je a f m)       (if (f (car a))           (append m (list (car a)))           m))     (if (null? (cdr z))         (je z f m)         (append (je z f m) (jg (cdr z) f))))            (if (q? x)      (append (list x) (jg z q?))      (append (list x) (jg z o?))))