{"title":"Problem 93","height":"190","blog_url":"https://jeneshicc.hatenadiary.org/","image_url":null,"html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fjeneshicc.hatenadiary.org%2Fentry%2F20081118%2F1227013594\" title=\"Problem 93 - \u843d\u66f8\u304d\u3001\u6642\u3005\u843d\u5b66\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","author_url":"https://blog.hatena.ne.jp/jeneshicc/","version":"1.0","description":"http://projecteuler.net/index.php?section=problems&id=93 \u3068\u308a\u3042\u3048\u305a\u7d20\u76f4\u306b\u5168\u751f\u6210\u3057\u3066\u3001\u63a2\u7d22\u3002 import Data.List import Data.Ratio perm [] = [[]] perm xs@(_:_) =concat[map (h:)$perm(delete h xs)|h<-xs] calc fs xs = concatMap (calc' fs) . perm $ xs calc' [f,g,h] [x,y,z,w] = [f (g x y) (h z w),f x(g y(h z w)),f x(g (h y z\u2026","provider_name":"Hatena Blog","url":"https://jeneshicc.hatenadiary.org/entry/20081118/1227013594","author_name":"jeneshicc","blog_title":"\u843d\u66f8\u304d\u3001\u6642\u3005\u843d\u5b66","width":"100%","provider_url":"https://hatena.blog","type":"rich","published":"2008-11-18 22:06:34","categories":["Project Euler","Haskell"]}