题目链接: 传送门 Minimum Inversion Number Time Limit: 1000MS     Memory Limit: 32768 K Description The inversion number of a given number sequence a1, a2, ..., an is the number of pairs (ai, aj) that satisfy i < j and ai > aj. For a given sequence of numbe…

Problem Description The inversion number of a given number sequence a1, a2, ..., an is the number of pairs (ai, aj) that satisfy i < j and ai > aj. For a given sequence of numbers a1, a2, ..., an, if we move the first m >= 0 numbers to the end of…

For a given sequence A={a0,a1,...an−1}A={a0,a1,...an−1}, the number of pairs (i,j)(i,j) where ai>ajai>aj and i<ji<j, is called the number of inversions. The number of inversions is equal to the number of swaps of Bubble Sort defined in the fol…

                                                                E. Infinite Inversions                                                                                          time limit per test 2 seconds                                            …

题目连接:http://acm.hdu.edu.cn/showproblem.php?pid=6318 Problem Description Long long ago, there was an integer sequence a.Tonyfang think this sequence is messy, so he will count the number of inversions in this sequence. Because he is angry, you will ha…

Swaps and Inversions Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 2315    Accepted Submission(s): 882 Problem Description Long long ago, there was an integer sequence a.Tonyfang think this se…

Minimum Inversion Number [题目链接]Minimum Inversion Number [题目类型]最小逆序数 线段树 &题意: 求一个数列经过n次变换得到的数列其中的最小逆序数 &题解: 先说一下逆序数的概念: 在一个排列中,如果一对数的前后位置与大小顺序相反,即前面的数大于后面的数,那末它们就称为一个逆序. 一个排列中逆序的总数就称为这个排列的逆序数.逆序数为偶数的排列称为偶排列:逆序数为奇数的排列称为奇排列. 如2431中,21,43,41,31是逆序,逆序数…

题目传送门 /* 求逆序数的四种方法 */ /* 1. O(n^2) 暴力+递推 法:如果求出第一种情况的逆序列,其他的可以通过递推来搞出来,一开始是t[1],t[2],t[3]....t[N] 它的逆序列个数是N个,如果把t[1]放到t[N]后面,逆序列个数会减少t[1]个,相应会增加N-(t[1]+1)个 */ #include <cstdio> #include <cstring> #include <algorithm> using namespace std;…

Minimum Inversion Number Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 17737    Accepted Submission(s): 10763 Problem Description The inversion number of a given number sequence a1, a2, ...,…

Minimum Inversion Number Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 11788    Accepted Submission(s): 7235 Problem Description The inversion number of a given number sequence a1, a2, ..., an…