CodeForces -163E :e-Government (AC自动机+DFS序+树状数组)
The best programmers of Embezzland compete to develop a part of the project called "e-Government" — the system of automated statistic collecting and press analysis.
We know that any of the k citizens can become a member of the Embezzland government. The citizens' surnames are a1, a2, ..., ak. All surnames are different. Initially all k citizens from this list are members of the government. The system should support the following options:
- Include citizen ai to the government.
- Exclude citizen ai from the government.
- Given a newspaper article text, calculate how politicized it is. To do this, for every active government member the system counts the number of times his surname occurs in the text as a substring. All occurrences are taken into consideration, including the intersecting ones. The degree of politicization of a text is defined as the sum of these values for all active government members.
Implement this system.
Input
The first line contains space-separated integers n and k (1 ≤ n, k ≤ 105) — the number of queries to the system and the number of potential government members.
Next k lines contain the surnames a1, a2, ..., ak, one per line. All surnames are pairwise different.
Next n lines contain queries to the system, one per line. Each query consists of a character that determines an operation and the operation argument, written consecutively without a space.
Operation "include in the government" corresponds to the character "+", operation "exclude" corresponds to "-". An argument of those operations is an integer between 1 and k — the index of the citizen involved in the operation. Any citizen can be included and excluded from the government an arbitrary number of times in any order. Including in the government a citizen who is already there or excluding the citizen who isn't there changes nothing.
The operation "calculate politicization" corresponds to character "?". Its argument is a text.
All strings — surnames and texts — are non-empty sequences of lowercase Latin letters. The total length of all surnames doesn't exceed 106, the total length of all texts doesn't exceed 106.
Output
For any "calculate politicization" operation print on a separate line the degree of the politicization of the given text. Print nothing for other operations.
Examples
7 3
a
aa
ab
?aaab
-2
?aaab
-3
?aaab
+2
?aabbaa
6
4
3
6
题意:有M个不同的单词,和N个操作。先给出M个单词,然后N操作,
操作1,删去第i个单词(如果已经删了,则忽略);
操作2,添加,亦然。
操作3,给出字符串S,查询当前存在的单词在字符串S种出现了多少次(可以重复统计)。
思路:对M个单词建立AC自动机,然后是fail树,对fail树求dfs序。
假设没有求fail树和dfs序,只有fail指针,我求S出现次数的时候,S在AC自动机上跑,对于每一个当前Si在AC自动机的Now位置,都向上累加个数,表示以i为结尾的字符串,出现了多少次。
建立了fail树后,x的fail指针是x的爸爸,那么fail出现的时候,x也出现。即x出现的时候,子树都会++;所以在树状数组上+1,-1;
得到dfs序,询问串S时,在AC自动机上面跑,累加树状数组的贡献。
准确性:因为在询问串AC自动机上面跑的时候,我跑的深度是最大的,对它有贡献的都利用fail树和数状数组更新了,做到了不重不漏。
#include<bits/stdc++.h>
using namespace std;
const int maxn=;
int ch[maxn][],cnt=; //trie树
int pos[maxn],st[maxn]; //在trie树的位置。
int Laxt[maxn],Next[maxn],To[maxn],tot; //fail树
int q[maxn],fail[maxn],head,tail; //fail树
int in[maxn],out[maxn],sum[maxn],times;//dfs序
char c[maxn];
char getopt() { char c=getchar(); while(c!='+'&&c!='-'&&c!='?') c=getchar(); return c;}
void addedge(int u,int v){ Next[++tot]=Laxt[u]; Laxt[u]=tot; To[tot]=v; }
int insert()
{
int L=strlen(c+),Now=;
for(int i=;i<=L;i++){
if(!ch[Now][c[i]-'a']) ch[Now][c[i]-'a']=++cnt;
Now=ch[Now][c[i]-'a'];
} return Now;
}
void buildfail()
{
for(int i=;i<;i++){
if(ch[][i]) q[++head]=ch[][i],fail[ch[][i]]=;
else ch[][i]=;
}
while(tail<head){
int Now=q[++tail];
for(int i=;i<;i++){
if(ch[Now][i]) {
q[++head]=ch[Now][i]; fail[ch[Now][i]]=ch[fail[Now]][i];
}
else ch[Now][i]=ch[fail[Now]][i];
}
}
for(int i=;i<=cnt;i++) addedge(fail[i],i);
}
void dfs(int u)
{
in[u]=++times;
for(int i=Laxt[u];i;i=Next[i]) dfs(To[i]);
out[u]=times;
}
void addsum(int x,int val){ while(x<=times){ sum[x]+=val; x+=(-x)&x;}}
int query(int x){ int res=;while(x){res+=sum[x];x-=(-x)&x;}return res;}
void solve()
{
int L=strlen(c+),Now=,ans=;
for(int i=;i<=L;i++){
Now=ch[Now][c[i]-'a'];
ans+=query(in[Now]);
}
printf("%d\n",ans);
}
int main()
{
int N,M,x,i,j;
scanf("%d%d",&N,&M);
for(i=;i<=M;i++){
st[i]=;
scanf("%s",c+);
pos[i]=insert();
}
buildfail();
dfs();
for(i=;i<=M;i++){
addsum(in[pos[i]],);
addsum(out[pos[i]]+,-);
}
for(i=;i<=N;i++){
char opt=getopt();
if(opt=='?'){
scanf("%s",c+);
solve();
}
else{
scanf("%d",&x);
if(opt=='+'){
if(st[x]==) continue;st[x]=;
addsum(in[pos[x]],);
addsum(out[pos[x]]+,-);
}
else {
if(st[x]==) continue; st[x]=;
addsum(in[pos[x]],-);
addsum(out[pos[x]]+,);
}
}
}
return ;
}
CodeForces -163E :e-Government (AC自动机+DFS序+树状数组)的更多相关文章
- BZOJ 2434: [Noi2011]阿狸的打字机( AC自动机 + DFS序 + 树状数组 )
一个串a在b中出现, 那么a是b的某些前缀的后缀, 所以搞出AC自动机, 按fail反向建树, 然后查询(x, y)就是y的子树中有多少是x的前缀. 离线, 对AC自动机DFS一遍, 用dfs序+树状 ...
- NOI 2011 阿狸的打字机 (AC自动机+dfs序+树状数组)
题目大意:略(太长了不好描述) 良心LOJ传送门 先对所有被打印的字符串建一颗Trie树 观察数据范围,并不能每次打印都从头到尾暴力建树,而是每遍历到一个字符就在Trie上插入这个字符,然后记录每次打 ...
- BZOJ_2434_[NOI2011]_阿狸的打字机_(AC自动机+dfs序+树状数组)
描述 http://www.lydsy.com/JudgeOnline/problem.php?id=2434 给出\(n\)个字符串,\(m\)个询问,对于第\(i\)个询问,求第\(x_i\)个字 ...
- BZOJ2434[Noi2011]阿狸的打字机——AC自动机+dfs序+树状数组
题目描述 阿狸喜欢收藏各种稀奇古怪的东西,最近他淘到一台老式的打字机.打字机上只有28个按键,分别印有26个小写英文字母和'B'.'P'两个字母. 经阿狸研究发现,这个打字机是这样工作的: l 输入小 ...
- 【BZOJ2434】[NOI2011]阿狸的打字机 AC自动机+DFS序+树状数组
[BZOJ2434][NOI2011]阿狸的打字机 Description 阿狸喜欢收藏各种稀奇古怪的东西,最近他淘到一台老式的打字机.打字机上只有28个按键,分别印有26个小写英文字母和'B'.'P ...
- BZOJ2434: [NOI2011]阿狸的打字机(AC自动机+dfs序+树状数组)
[NOI2011]阿狸的打字机 题目链接:https://www.luogu.org/problemnew/show/P2414 题目背景 阿狸喜欢收藏各种稀奇古怪的东西,最近他淘到一台老式的打字机. ...
- BZOJ 2434 阿狸的打字机(ac自动机+dfs序+树状数组)
题意 给你一些串,还有一些询问 问你第x个串在第y个串中出现了多少次 思路 对这些串建ac自动机 根据fail树的性质:若x节点是trie中root到t任意一个节点的fail树的祖先,那么x一定是y的 ...
- BZOJ_3881_[Coci2015]Divljak_AC自动机+dfs序+树状数组
BZOJ_3881_[Coci2015]Divljak_AC自动机+dfs序+树状数组 Description Alice有n个字符串S_1,S_2...S_n,Bob有一个字符串集合T,一开始集合是 ...
- Codeforces Round #381 (Div. 2) D dfs序+树状数组
D. Alyona and a tree time limit per test 2 seconds memory limit per test 256 megabytes input standar ...
随机推荐
- VueJS组件之全局组件与局部组件
全局组件 所有实例都能用全局组件. HTML <!DOCTYPE html> <html> <head> <meta charset="utf-8& ...
- 38: 立方根getCubeRoot
题目描述:计算一个数字的立方根,不使用库函数 •接口说明 原型:public static double getCubeRoot(double input) 输入:double 待求解参数 返回值:d ...
- kotlin 语言入门指南(一)--基础语法
基于官网的Getting Start的基础语法教程部分,一共三节,这篇是第一节,翻译如下: 基础语法 定义一个包 包的声明必须放在文件头部: package my.demo import java.u ...
- uboot生成随机的MAC地址
转载:http://blog.chinaunix.net/uid-25885064-id-3303132.html 在使用U-boot时,有个问题就是MAC地址的设置,如果MAC地址相同的两块开发板在 ...
- ssh无密码登陆权威指南
[0]写在前面 由于ssh 实现的是免密码登陆,大致步骤是: 0.1) client通过ssh登陆到server: 0.2) server检查家目录下的.ssh文件, 并发送公钥文件 authoriz ...
- 【剑指Offer学习】【面试题58:二叉树的下一个结点】
题目:给定一棵二叉树和当中的一个结点.怎样找出中序遍历顺序的下一个结点?树中的结点除了有两个分别指向左右子结点的指针以外,另一个指向父节点的指针. 解题思路 假设一个结点有右子树.那么它的下一个结点就 ...
- JBoss AS 7之域名直接訪问配置(The Return Of The King)
1.6域名直接訪问配置 部署JBoss的时候,默认情况下訪问是须要加项目名字才可以訪问的. 可是怎样才可以"IP+port"訪问呢?以下将解说怎样配置. 配置域名訪问须要在项目以下 ...
- MySQL 事务1
本人应用的MySQL的版本为:5.6.22
- 【BZOJ3217】ALOEXT 替罪羊树+Trie树
[BZOJ3217]ALOEXT Description taorunz平时最喜欢的东西就是可移动存储器了……只要看到别人的可移动存储器,他总是用尽一切办法把它里面的东西弄到手. 突然有一天,taor ...
- Vue中表单校验
1.安装校验插件vee-validate npm install vee-validate --save 2.在main.js中引用插件 // 表单校验 import VeeValidate, { V ...