Copyright (c) 2019. The copyright is reserved by Ghode of Harbin Institute of Technology. Users are free to copy, change or remove. Because no one will read this. Only I know is that Repeaters are the best of the world.Only I know is that Repeaters are the best of the world. Only I know is that Repeaters are the best of the world. Maybe a long copyright text seems professional. Therefore this text will be a bit lengthy. However,the author seems to be afraid that one day, this text may be uploaded to business projects. That is the time you can contact with author via email ghode@cirnocraft.im or directly ignore this, which will be interesting.