摘要：
Party at Hali-Bula UVA - 1220 题意： 公司里有n（n<=200）个人形成一个树状结构， 要求尽量选多的人，但不能同时选择一个人和他的直属上司，文最多能选多少人，以及是否方案唯一。 阅读全文
摘要：
Almost Arithmetical Progression CodeForces - 255C Gena loves sequences of numbers. Recently, he has discovered a new type of sequences which he called 阅读全文
摘要：
Anniversary party HDU - 1520 There is going to be a party to celebrate the 80-th Anniversary of the Ural State University. The University has a hierar 阅读全文