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A. Substring and SubsequenceOne day Polycarpus got hold of two non-empty stringssandt, consisting of lowercase Latin letters. Polycarpus is quite good... 阅读全文
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Yet another Number SequenceLet’s define another number sequence, given by the following function:f(0) = af(1) = bf(n) = f(n − 1) + f(n − 2), n... 阅读全文
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B. Word CutLet's consider one interesting word game. In this game you should transform one word into another through special operations.Let's say we h... 阅读全文
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Rock-Paper-ScissorsNikephoros and Polycarpus play rock-paper-scissors. The loser gets pinched (not too severely!).Let us remind you the rules of this ... 阅读全文