{"description":"Inscribed circles of triangles with one angle of 60 degrees Problem 195 - Project Euler \u524d\u306b\u3084\u3063\u305f\u554f\u984c\u3067\u4f3c\u305f\u3088\u3046\u306a\u3082\u306e\u304c\u3042\u3063\u305f(\u305f\u3057\u304b\uff0c\u30c8\u30ea\u30c1\u30a7\u30ea\u306e\u4e09\u89d2\u5f62\u3060\u3063\u305f\u6c17\u304c\u3059\u308b)\uff0e \u306f\u3058\u3081\u306f\uff0c\u5916\u63a5\u5186\u3060\u3068\u601d\u3063\u3066\u3044\u305f\uff0e import Control.Monad (guard) p195 r = sum $ do m <- [1..floor u] d <- [1..min (m-1).floor $ u / fromIntegral m] guard $ gcd m d == 1 return.floor.((/) u\u2026","blog_url":"https://jeneshicc.hatenadiary.org/","published":"2009-02-07 21:17:54","url":"https://jeneshicc.hatenadiary.org/entry/20090207/1234009074","provider_name":"Hatena Blog","categories":["Project Euler","Haskell"],"version":"1.0","author_name":"jeneshicc","height":"190","width":"100%","provider_url":"https://hatena.blog","author_url":"https://blog.hatena.ne.jp/jeneshicc/","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fjeneshicc.hatenadiary.org%2Fentry%2F20090207%2F1234009074\" title=\"Problem 195 - \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>","title":"Problem 195","type":"rich","blog_title":"\u843d\u66f8\u304d\u3001\u6642\u3005\u843d\u5b66","image_url":null}