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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 given s 阅读全文
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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 task is simply to cal 阅读全文
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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. F 阅读全文
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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 cou 阅读全文
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Zhejiang University has 40000 students and provides 2500 courses. Now given the registered course list of each student, you are supposed to output the 阅读全文
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The task is really simple: given N exits on a highway which forms a simple cycle, you are supposed to tell the shortest distance between any pair of e 阅读全文