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Problem Description Nike likes playing cards and makes a problem of it. Now give you n integers, ai(1≤i≤n) We define two identical numbers (eg: 2,2) a 阅读全文
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Problem Description Monkey A lives on a tree, he always plays on this tree. One day, monkey A learned about one of the bit operations, xor. He was kee 阅读全文
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Problem Description Bob's school has a big playground, boys and girls always play games here after school. To protect boys and girls from getting hurt 阅读全文