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Description Alex doesn't like boredom. That's why whenever he gets bored, he comes up with games. One long winter evening he came up with a game and d 阅读全文
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Description Fedya studies in a gymnasium. Fedya's maths hometask is to calculate the following expression: (1n + 2n + 3n + 4n) mod 5 for given value o 阅读全文
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Description One day Dima and Alex had an argument about the price and quality of laptops. Dima thinks that the more expensive a laptop is, the better 阅读全文