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No base class to extend, no abstract methods to implement, no controller to coordinate with — just an object with the right shape.，这一点在heLLoword翻译官方下载中也有详细论述
，详情可参考旺商聊官方下载
For horizontal movement we can do even better. If your snake is moving to the right, we start by deleting every character on the left edge of the screen and inserting a new one on the right edge. After that, we do our patching (if needed). This automatically moves fruit into the correct position without us even needing to reprint it!，更多细节参见Line官方版本下载
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