题目传送门 题意:问区间内x的出现的次数分析:莫队算法:用一个cnt记录x的次数就可以了.还有二分查找的方法 代码: #include <cstdio> #include <algorithm> #include <cmath> #include <cstring> using namespace std; const int MAXN = 1e5 + 10; const int INF = 0x3f3f3f3f; struct Data { int b,…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=6278 Time Limit: 6000/3000 MS (Java/Others) Memory Limit: 132768/132768 K (Java/Others) Problem Description The h-index of an author is the largest h where he has at least h papers with citations not les…

题目描述 给一个长度为n的非负整数序列A1,A2,…,An.现有m个询问,每次询问给出l,r,p,k,问满足l<=i<=r且Ai mod p = k的值i的个数. 输入 第一行两个正整数n和m. 第二行n个数,表示A1,A2,…,An. 以下m行,每行四个数分别表示l,r,p,k.满足1<=l<=r<=n. 输出 对于每个询问,输出一行,表示可行值i的个数. 样例输入 5 2 1 5 2 3 7 1 3 2 1 2 5 3 0 样例输出 2 1 题解 根号分治+STL-vec…

题意与分析 题意是这样的,给定一颗节点有权值的树,然后给若干个询问,每次询问让你找出一条链上有多少个不同权值. 写这题之前要参看我的三个blog:Codeforces Round #326 Div. 2 E(树上利用倍增求LCA).Codeforces Round #340 Div. 2 E(朴素莫队)和BZOJ-1086(树的分块),然后再看这几个Blog-- 参考A:https://blog.sengxian.com/algorithms/mo-s-algorithm 参考B:https:/…

题意: 给出一棵\(n(n \leq 4 \times 10^4)\)个节点的树,每个节点上有个权值,和\(m(m \leq 10^5)\)个询问. 每次询问路径\(u \to v\)上有多少个权值不同的点. 分析: 树分块 首先将树分块,每块的大小为\(\sqrt{n}\)左右. 然后将询问离线处理,按照区间上的莫队算法将询问按块排序. 这里有一道裸的树分块的题目. 树上的路径转移 定义\(S(u,v)\)表示路径\(u \to v\)上的点集,定义\(\bigoplus\)为集合的对称差,类…

Sona Time Limit:5000MS     Memory Limit:65535KB     64bit IO Format: Submit Status Practice NBUT 1457 Appoint description:  Description Sona, Maven of the Strings. Of cause, she can play the zither. Sona can't speak but she can make fancy music. Her…

XOR and Favorite Number time limit per test: 4 seconds memory limit per test: 256 megabytes input: standard input output: standard output Bob has a favorite number k and ai of length n. Now he asks you to answer m queries. Each query is given by a pa…

http://acm.fzu.edu.cn/problem.php?pid=2226 信心题,还说是信心题,题目给的真好.但是一点都不像信心题. 又是一个新的算法,莫队算法 莫队算法是一个用数组就可以轻易实现的神奇数据结构,可以处理一类无修改的离线区间查询问题(PS:暂时还没有遇到莫队解决更新区间查询的问题) 莫队算法可以在O(1),实现[l, r]到[l, r±1] / [l±1, r]的转移,然后我们就可以对所有查询分sqrt(n)块,把每个查询所在的块号当做第一关键字,右端点作为第二关键字…

[1457] Sona 时间限制: 5000 ms 内存限制: 65535 K 问题描述 Sona, Maven of the Strings. Of cause, she can play the zither. Sona can't speak but she can make fancy music. Her music can attack, heal, encourage and enchant. There're an ancient score(乐谱). But because i…

E. XOR and Favorite Number 题目连接: http://www.codeforces.com/contest/617/problem/E Descriptionww.co Bob has a favorite number k and ai of length n. Now he asks you to answer m queries. Each query is given by a pair li and ri and asks you to count the n…