摘要：
题目 One cow from each of N farms (1 ≤ N ≤ 1000) conveniently numbered 1..N is going to attend the big cow party to be held at farm #X (1 ≤ X ≤ N). A to 阅读全文
摘要：
题目 In Land waterless, water is a very limited resource. People always fight for the biggest source of water. Given a sequence of water sources with a1 阅读全文