{"published":"2009-12-30 03:05:07","blog_url":"https://firewood.hatenadiary.jp/","author_url":"https://blog.hatena.ne.jp/firewood/","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Ffirewood.hatenadiary.jp%2Fentry%2F20091230%2F1262109907\" title=\"SICP\u81ea\u7fd2 - firewood&#39;s diary\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","height":"190","author_name":"firewood","width":"100%","blog_title":"firewood's diary","version":"1.0","url":"https://firewood.hatenadiary.jp/entry/20091230/1262109907","title":"SICP\u81ea\u7fd2","provider_name":"Hatena Blog","provider_url":"https://hatena.blog","type":"rich","image_url":null,"categories":[],"description":"SICP Lite #9\u306b\u884c\u304b\u306a\u304b\u3063\u305f\u306e\u3067\u81ea\u7fd2\u3002 DrScheme\u306b\u3066\u3042\u308b\u7bc4\u56f2\u306e\u7d20\u6570\u3092\u6c42\u3081\u3066\u3001\u7d50\u679c\uff08\u500b\u6570\uff09\u3068\u5b9f\u884c\u6642\u9593\u3092\u8868\u793a\u3059\u308b\u3002divides?\u3068prime?\u306f\u3042\u308b\u3068\u3057\u3066 (define (search-for-primes start end) (define (next n) (+ n (if (divides? 2 n) 1 2))) (define (loop start end result) (if (> start end) result (loop (next start) end (+ result (if (prime? start) 1 0))))) (loop star\u2026"}