AC_automaton 模板

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Code

// by spli#include<cstdio>#include<iostream>#include<algorithm>#include<cstring>#include<queue>using namespace std;const int N=1000010;int n;char s[N];int tot;struct AC_automaton{    int fail;    int to[26];    int end;}ac[N];queue<int>q;int ans;void build(){    int now=0,ch;    int len=strlen(s+1);    for(int i=1;i<=len;++i){        ch=s[i]-'a';        if(!ac[now].to[ch]) ac[now].to[ch]=++tot;        now=ac[now].to[ch];    }    ac[now].end++;}void getfail(){    for(int i=0;i<26;++i)         if(ac[0].to[i]) q.push(ac[0].to[i]),ac[ac[0].to[i]].fail=0;    while(!q.empty()){        int u=q.front();        q.pop();        for(int i=0;i<26;++i){            int v=ac[u].to[i];            if(v) ac[v].fail=ac[ac[u].fail].to[i],q.push(v);            else ac[u].to[i]=ac[ac[u].fail].to[i];        }    }}void query(){    int now=0,ch;    int len=strlen(s+1);    for(int i=1;i<=len;++i){        ch=s[i]-'a';//写成-'0'身败名裂        now=ac[now].to[ch];        for(int j=now;j&&ac[j].end!=-1;j=ac[j].fail){            ans+=ac[j].end;            ac[j].end=-1;        }    }}int main(){    scanf("%d",&n);    for(int i=1;i<=n;++i){        scanf("%s",s+1);        build();    }    getfail();    scanf("%s",s+1);    query();    cout<<ans;    return 0;}