摘要：
Recently Polycarp started to develop a text editor that works only with correct bracket sequences (abbreviated as CBS). Note that a bracket sequence i 阅读全文
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TT and FF are ... friends. Uh... very very good friends -________-b FF is a bad boy, he is always wooing TT to play the following game with him. This 阅读全文
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The problem is about Mr.BG who is a great hunter. Today he has gone to a dense forest for hunting and killing animals. Sadly, he has only one bullet i 阅读全文
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Mr. Ant has 3 boxes and the infinite number of marbles. Now he wants to know the number of ways he can put marbles in these three boxes when the follo 阅读全文
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To make competitive programmers of BUBT, authority decide to take regular programming contest. To make this contest more competitive and fruitful ther 阅读全文