摘要：
Problem Description Doge, tired of being a popular image on internet, is considering moving to another city for a new way of life. In his country th... 阅读全文
摘要：
Problem DescriptionBob is travelling in Xi’an. He finds many secret tunnels beneath the city. In his eyes, the city is a grid. He can’t enter a grid w... 阅读全文
摘要：
Problem Description Recently, doge starts to get interested in a strange problem: whether there exists a string A following all the rules below: 1.T... 阅读全文