摘要： 描述 The doggie found a bone in an ancient maze, which fascinated him a lot. However, when he picked it up, the maze began to shake, and the doggie coul 阅读全文

摘要： Problem Statement On a two-dimensional plane, there are N red points and N blue points. The coordinates of the i-th red point are (ai,bi), and the coo 阅读全文

摘要： 描述 Consider a group of N students and P courses. Each student visits zero, one or more than one courses. Your task is to determine whether it is possi 阅读全文