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题目 Given a stack which can keep M numbers at most. Push N numbers in the order of 1, 2, 3, ..., N and pop randomly. You are supposed to tell if a give 阅读全文
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题目 Given two strings S1 and S2 , S=S1 −S2 is defined to be the remaining string after taking all the characters in S2 from S1 . Your 阅读全文
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题目 The task is simple: given any positive integer N, you are supposed to count the total number of 1's in the decimal form of the integers from 1 to N 阅读全文
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题目 Eva loves to collect coins from all over the universe, including some other planets like Mars. One day she visited a universal shopping mall which 阅读全文
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题目 Zhejiang University has 40,000 students and provides 2,500 courses. Now given the registered course list of each student, you are supposed to outpu 阅读全文