jeneshicc https://blog.hatena.ne.jp/jeneshicc/ 落書き、時々落学 https://jeneshicc.hatenadiary.org/ Project Euler Haskell Inscribed circles of triangles with one angle of 60 degrees Problem 195 - Project Euler 前にやった問題で似たようなものがあった(たしか，トリチェリの三角形だった気がする)． はじめは，外接円だと思っていた． 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… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fjeneshicc.hatenadiary.org%2Fentry%2F20090207%2F1234009074" title="Problem 195 - 落書き、時々落学" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2009-02-07 21:17:54 rich https://jeneshicc.hatenadiary.org/entry/20090207/1234009074 1.0 100%