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E. Digit Tree time limit per test 3 seconds memory limit per test 256 megabytes input standard input output standard output E. Digit Tree time limit p 阅读全文
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Dicription You have a connected directed graph.Let $d(x)$ be the length of the shortest path from $1$ to $x$.Specially $d(1)=0$.A graph is good if the 阅读全文
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Discription Priests of the Quetzalcoatl cult want to build a tower to represent a power of their god. Tower is usually made of power-charged rocks. It 阅读全文