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Bobo has a tree with n vertices numbered by 1,2,…,n and (n-1) edges. The i-th vertex has color c i, and the i-th edge connects vertices a i and b i. L 阅读全文
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You are given a rooted undirected tree consisting of nn vertices. Vertex 11 is the root. Let's denote a depth array of vertex xx as an infinite sequen 阅读全文
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You are given a rooted tree with root in vertex 1. Each vertex is coloured in some colour. Let's call colour c dominating in the subtree of vertex v i 阅读全文
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Once in a forest, there lived N aggressive monkeys. At the beginning, they each does things in its own way and none of them knows each other. But monk 阅读全文
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在一个忍者的帮派里，一些忍者们被选中派遣给顾客，然后依据自己的工作获取报偿。在这个帮派里，有一名忍者被称之为 Master。除了 Master以外，每名忍者都有且仅有一个上级。为保密，同时增强忍者们的领导力，所有与他们工作相关的指令总是由上级发送给他的直接下属，而不允许通过其他的方式发送。现在你要招 阅读全文