摘要：
Young Timofey has a birthday today! He got kit of n cubes as a birthday present from his parents. Every cube has a number ai, which is written on it. 阅读全文
摘要：
解题思路： 一个乱序序列的 逆序数 = 在只允许相邻两个元素交换的条件下,得到有序序列的交换次数 直接求逆序数 把S[i]和s[i+1~n]的元素逐个比较，如果s[i] > s[k] (k∈[i+1,n]) 则逆序数t++ O(n^2)算法 阅读全文