We prove a conjecture of Fox, Huang, and Lee that characterizes directed graphs that have constant density in all tournaments: they are disjoint unions of trees that are each constructed in a certain recursive way.

中文翻译：

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公正有向图

我们证明了 Fox、Huang 和 Lee 的猜想，该猜想表征了所有锦标赛中密度恒定的有向图：它们是树的不相交联合，每个树都以某种递归方式构造。