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E. Interesting Graph and Apples 题目连接： http://www.codeforces.com/contest/9/problem/E Description Hexadecimal likes drawing. She has drawn many graphs a 阅读全文
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D. How many trees? 题目连接： http://www.codeforces.com/contest/9/problem/D Description In one very old text file there was written Great Wisdom. This Wisd 阅读全文
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C. Hexadecimal's Numbers 题目连接： http://www.codeforces.com/contest/9/problem/C Description One beautiful July morning a terrible thing happened in Mainf 阅读全文
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B. Running Student 题目连接： http://www.codeforces.com/contest/9/problem/B Description And again a misfortune fell on Poor Student. He is being late for a 阅读全文
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A. Die Roll 题目连接： http://www.codeforces.com/contest/9/problem/A Description Yakko, Wakko and Dot, world famous animaniacs, decided to rest from acting 阅读全文