練習問題4.45 写真参照 練習問題4.46 ずっと存在しない prepositional-phrase を探し求めて無限ループ回って死ぬ。 練習問題4.47 無限ループ回って死ぬ。 verbs だ！ →後ろに前置詞句ついてる、違うじゃん！ →verb-phrase だ！ →じゃあ (parse-verb-phrase) …

練習問題4.44 8×8 面倒なので 4×4 で。 #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 …

練習問題4.41 (define (generate-list n) (define (pow n k) (if (= k 0) 1 (* n (pow n (- k 1))) ) ) (define (int-to-list m n k) (if (= k 0) (list) (cons (remainder m n) (int-to-list (/ (- m (remainder m n)) n) n (- k 1))) ) ) (define (list-ge…

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 ))…

練習問題4.35 (define (an-integer-between low high) (require (<= low high)) (amb low (an-integer-between (+ low 1) high))) 練習問題4.36 (define (a-pythagorean-triple-between) (let ((high (an-integer-starting-from 1))) (let ((i (an-integer-b…