[hdu2222] [AC自动机模板] Keywords Search [AC自动机]

AC自动机模板，注意！ch,Fail,lab数组的大小不是n而是节点个数，需要认真计算！

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <ctime>
#include <cstdlib>
#include <queue>

using namespace std;

int    cnt;
int    ch[1100000][26],Fail[1100000],lab[1100000];
char    str[1100000],S[1100000];

void    Add(const char * s)
{
    int    p=0,i;
    for(i=1;s[i];++i)
    {
        if(!ch[p][s[i]-97])ch[p][s[i]-97]=++cnt;
        p=ch[p][s[i]-97];
    }
    lab[p]++;
    return ;
}

void    Build()
{
    int    i,t;
    queue<int>    Q;
    Q.push(0);
    while(!Q.empty())
    {
        t=Q.front();Q.pop();
        for(i=0;i<26;++i)
        {
            if(ch[t][i])
            {
                Q.push(ch[t][i]);
                Fail[ch[t][i]]=t?ch[Fail[t]][i]:0;
            }
            else    ch[t][i]=ch[Fail[t]][i];
        }
    }
    return ;
}

int main()
{
    int    T,n,i;

    scanf("%d",&T);
    while(T--)
    {
        memset(Fail,0,sizeof(Fail));
        memset(ch,0,sizeof(ch));
        memset(lab,0,sizeof(lab));
        cnt=0;
        scanf("%d",&n);
        for(i=1;i<=n;++i)
        {
            scanf("%s",str+1);
            Add(str);
        }
        Build();
        scanf("%s",S+1);
        int    p=0,Ans=0;
        for(i=1;S[i];++i)
        {
            p=ch[p][S[i]-97];
            if(lab[p])
            {
                int    pp=p;
                while(pp)Ans+=lab[pp],lab[pp]=0,pp=Fail[pp];
            }
        }
        printf("%d
",Ans);
    }

    return 0;
}