https://tripdancer0916.hatenablog.com/entry/2019/05/03/Average_Controllability%E3%81%AE%E6%B0%97%E6%8C%81%E3%81%A1%E3%82%92%E7%90%86%E8%A7%A3%E3%81%99%E3%82%8B%EF%BC%88%E8%A8%88%E7%AE%97%E3%83%A1%E3%83%A2%EF%BC%892019-05-03T18:21:30+09:00