SICPゼミ第57回[tube_worm死す]
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-between 1 high ))) (let ((j (an-integer-between i high ))) (let ((k high)) (require (= (+ (* i i) (* j j)) (* k k))) (list i j k))))))
練習問題4.37
予想に反してBenのアルゴリズムのほうが効率が良い.
4.35のアルゴリズムが調べるのはn個の数字から3個を選ぶやり方なので.
Benのものは個の数字から2個を選ぶやり方なので.