原题poj 2299:http://poj.org/problem?id=2299 题意,给你一个数组,去统计它们的逆序数,由于题目中说道数组最长可达五十万,那么O(n^2)的排序算法就不要再想了,归并排序~~~ 这里列出归并的解法: #include"iostream" using namespace std; const int maxn=500000+10; int T[maxn]; int a[maxn]; long long sum; void merge_sort(int…
Description There are N<tex2html_verbatim_mark> marbles, which are labeled 1, 2,..., N<tex2html_verbatim_mark> . The N<tex2html_verbatim_mark> marbles are put in a circular track in an arbitrary order. In the top part of the track ther…
A permutation on the integers from 1 to n is, simply put, a particular rearrangement of these integers. Your task is to generate a given permutation from the initial arrangement 1, 2, 3, . . . , n using only two simple operations. • Operation 1: You…
Description Shaass has n books. He wants to make a bookshelf for all his books. He wants the bookshelf's dimensions to be as small as possible. The thickness of the i-th book is ti and its pages' width is equal to wi. The thickness of each book is ei…
Description John Doe is a famous DJ and, therefore, has the problem of optimizing the placement of songs on his tapes. For a given tape and for each song on that tape John knows the length of the song and the frequency of playing that song. His pro…
