2018-02-07から1日間の記事一覧
練習問題4.38 #lang racket (require sicp-pict) (define (require p) (if (not p) (amb) 0)) (define (distinct? items) (cond ((null? items) true) ((null? (cdr items)) true) ((member (car items) (cdr items)) false) (else (distinct? (cdr items ))…