摘要：
Greedy Gift GiversA group of NP (2 ≤ NP ≤ 10) uniquely named friends hasdecided to exchange gifts of money. Each of these friends might ormight not gi... 阅读全文
摘要：
Your Ride Is HereIt is a well-known fact that behind every good comet is a UFO. TheseUFOs often come to collect loyal supporters from here on Earth.Un... 阅读全文