{"provider_name":"Hatena Blog","description":"http://www.haskell.org/haskellwiki/99_questions/11_to_20 H99 Question 14 \u65e5\u672c\u8a9e\u8a33 \u30ea\u30b9\u30c8\u306e\u8981\u7d20\u3092\u91cd\u8907\u3055\u305b\u306a\u3055\u3044\u3002 > dupli [1, 2, 3] [1,1,2,2,3,3] \u3053\u308c\u306f\u7c21\u5358\u3067\u3059\u306d\u3002 dupli :: [a] -> [a] dupli = concatMap (\\x -> ([x,x])) dupli' [] = [] dupli' (x:xs) = x:x:(dupli xs) \u6a21\u7bc4\u89e3\u7b54\u3082\u3053\u3093\u306a\u611f\u3058\u3067\u3057\u305f\u3002 concatMap\u4fbf\u5229\u3002Question 12\u3067\u66f8\u3044\u305f\u3068\u304a\u308a\u3001\u4e2d\u306e\u30ea\u30b9\u30c8\u540c\u58eb\u3092\u9023\u7d50\u3055\u305b\u3066\u3001\u4e2d\u306e\u8981\u7d20\u2026","author_name":"ugnom","categories":["Haskell","H99"],"height":"190","url":"https://ugnom.hatenablog.com/entry/2013/12/20/095223","type":"rich","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fugnom.hatenablog.com%2Fentry%2F2013%2F12%2F20%2F095223\" title=\" Haskell H99 Question 14 - \u3080\u305a\u304b\u3057\u3081\u306e\u30d1\u30bd\u30b3\u30f3\u52c9\u5f37\u306e\u8a18\u9332\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","image_url":null,"title":" Haskell H99 Question 14","published":"2013-12-20 09:52:23","blog_url":"https://ugnom.hatenablog.com/","blog_title":"\u3080\u305a\u304b\u3057\u3081\u306e\u30d1\u30bd\u30b3\u30f3\u52c9\u5f37\u306e\u8a18\u9332","width":"100%","version":"1.0","author_url":"https://blog.hatena.ne.jp/ugnom/","provider_url":"https://hatena.blog"}