AC自动机板子（from. qwer）

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#include <cstdio>#include <cstring>#include <cstdlib>#include <algorithm>#include <iostream>#include <string>#include <queue>using namespace std;const int N=510000;struct Tri{    int Next[N][26], fail[N], val[N], root, L;    void init() {L = 0;root = newnode();}    int newnode()    {        for(int i = 0;i < 26;i++) Next[L][i] = -1;        val[L++] = 0;        return L - 1;    }    void insert(char s[])    {        int len = strlen(s), cur = root;        for(int i = 0;i < len;i++)        {            if(Next[cur][s[i]-'a'] == -1)                Next[cur][s[i]-'a'] = newnode();            cur = Next[cur][s[i]-'a'];        }        val[cur]++;    }    void build()    {        queue<int>Q;        fail[root] = root;        for(int i = 0;i < 26;i++)            if(Next[root][i] == -1) Next[root][i] = root;            else            {                fail[Next[root][i]] = root;                Q.push(Next[root][i]);            }        while(!Q.empty())        {            int cur = Q.front(); Q.pop();            for(int i = 0;i < 26;i++)                if(Next[cur][i] == -1)                    Next[cur][i] = Next[fail[cur]][i];                else                {                    fail[Next[cur][i]]=Next[fail[cur]][i];                    Q.push(Next[cur][i]);                }        }    }    int query(char s[])    {        int len = strlen(s), cur = root, res = 0;        for(int i = 0;i < len;i++)        {            cur = Next[cur][s[i]-'a'];            int tmp = cur;            while (tmp != root)            {                res += val[tmp];                val[tmp] = 0;                tmp = fail[tmp];            }        }        return res;    }};char s[N];Tri AC;int n;int main(){      scanf("%d",&n);      AC.init();      for(int i = 0;i < n;i++)      {          scanf("%s",s);          AC.insert(s);      }      AC.build();      scanf("%s",s);      printf("%d\n",AC.query(s));      return 0;}
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