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传送门：http://poj.org/problem?id=2299In this problem, you have to analyze a particular sorting algorithm. The algorithm processes a sequence of n distinct integers by swapping two adjacent sequence elem...

树状数组其初衷是解决数据压缩里的累积频率（Cumulative Frequency）的计算问题，现多用于高效计算数列的前缀和， 区间和。它可以以 {\displaystyle O(\log n)} O(\log n)的时间得到任意前缀和 {\displaystyle \sum _{i=1}^{j}A[i],1<=j<=N} {\displaystyle \sum _{i=1}^{j}A...

传送门：http://acm.hdu.edu.cn/showproblem.php?pid=1556//简单树状数组练习#include<iostream>#include<cstdio>#include<string>using namespace std;const int maxn =1e5+10;int tree[maxn];int n;...