摘要：
Given a list of N integers A1, A2, A3,...AN, there's a famous problem to count the number of inversions in it. An inversion is defined as a pair of in 阅读全文
摘要：
Problem Description Ignatius has just come back school from the 30th ACM/ICPC. Now he has a lot of homework to do. Every teacher gives him a deadline 阅读全文