摘要： Problem Description：Given an N*N matrix with each entry equal to 0 or 1. You can swap any two rows or any two columns. Can you find a way to make all ... 阅读全文

摘要： Description：Every time it rains on Farmer John's fields, a pond forms over Bessie's favorite clover patch. This means that the clover is covered by wa... 阅读全文

摘要： Description：There are a group of students. Some of them may know each other, while others don't. For example, A and B know each other, B and C know ea... 阅读全文

摘要： Problem Description：On Octorber 21st, HDU 50-year-celebration, 50-color balloons floating around the campus, it's so nice, isn't it? To celebrate this... 阅读全文

摘要： Description：In the second year of the university somebody started a study on the romantic relations between the students. The relation "romantically i... 阅读全文

摘要： Problem Description：Suppose that we have a square city with straight streets. A map of a city is a square board with n rows and n columns, each repres... 阅读全文

摘要： Description：On a grid map there are n little men and n houses. In each unit time, every little man can move one unit step, either horizontally, or ver... 阅读全文

摘要： Problem Description：传说在遥远的地方有一个非常富裕的村落,有一天,村长决定进行制度改革：重新分配房子。这可是一件大事,关系到人民的住房问题啊。村里共有n间房间,刚好有n家老百姓,考虑到每家都要有房住（如果有老百姓没房子住的话，容易引起不安定因素），每家必须分配到一间房子且只能得到... 阅读全文

摘要： Description：A network administrator manages a large network. The network consists of N computers and M links between pairs of computers. Any pair of c... 阅读全文

摘要： Description：A number of schools are connected to a computer network. Agreements have been developed among those schools: each school maintains a list ... 阅读全文