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