摘要：Do you know what is called ``Coprime Sequence''? That is a sequence consists of nn positive integers, and the GCD (Greatest Common Divisor) of them is 阅读全文

摘要：Note: this is a harder version of Mirrored string I. The gorillas have recently discovered that the image on the surface of the water is actually a re 阅读全文

摘要：Description Misha and Vanya have played several table tennis sets. Each set consists of several serves, each serve is won by one of the players, he re 阅读全文