摘要：
Chilly Willy loves playing with numbers. He only knows prime numbers that are digits yet. These numbers are 2, 3, 5 and 7. But Willy grew rather bored 阅读全文
摘要：
Dima got into number sequences. Now he's got sequence a1, a2, ..., an, consisting of n positive integers. Also, Dima has got a function f(x), which ca 阅读全文
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Polar bears Menshykov and Uslada from the zoo of St. Petersburg and elephant Horace from the zoo of Kiev decided to build a house of cards. For that t 阅读全文
摘要：
Bob is a strategy game programming specialist. In his new city building game the gaming environment is as follows: a city is built up by areas, in whi 阅读全文