摘要：
Ping pong Description N (3 ≤ N ≤ 20000) ping pong players live along a west-east street(consider the street as a line segment). Each player has a uniq 阅读全文
摘要：
K Smallest Sums Description You’re given k arrays, each array has k integers. There are k k ways to pick exactly one element in each array and calcula 阅读全文