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题目: Ugly numbers are numbers whose only prime factors are 2, 3 or 5. The sequence 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, ... shows the first 11 ugly numb 阅读全文
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Now our hero finds the door to the BEelzebub feng5166. He opens the door and finds feng5166 is about to kill our pretty Princess. But now the BEelzebu 阅读全文
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Colonel has n badges. He wants to give one badge to every of his n soldiers. Each badge has a coolness factor, which shows how much it's owner reached 阅读全文
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You are given a string consisting of parentheses () and []. A string of this type is said to be correct: (a) if it is the empty string (b) if A and B 阅读全文
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原题: The local tradition is that every train arriving from the direction A continues in the direction B with coaches reorganized in some way. Assume th 阅读全文