摘要：
Misha and Grisha are funny boys, so they like to use new underground. The underground has n stations connected with n - 1 routes so that each route co 阅读全文
摘要：
n people are standing on a coordinate axis in points with positive integer coordinates strictly less than 106. For each person we know in which direct 阅读全文
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It's hard times now. Today Petya needs to score 100 points on Informatics exam. The tasks seem easy to Petya, but he thinks he lacks time to finish th 阅读全文
摘要：
It's one more school day now. Sasha doesn't like classes and is always bored at them. So, each day he invents some game and plays in it alone or with 阅读全文