[HDU2222]Keywords Search（AC自动机）

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AC自动机模板

#include <cstdio>#include <queue>#include <cstring>#define N 10000*50+10using namespace std;char st[N],ss[1000005];int tot=0,ch[N][30],fail[N],is_end[N];bool visit[N];void trie(){int now=0,l=strlen(st);for (int i=0;i<l;i++)  {  int x=st[i]-'a';  if (!ch[now][x]) ch[now][x]=++tot;  now=ch[now][x];  }is_end[now]++;}void sp(){int i;queue <int> q;for (i=0;i<26;i++)  if (ch[0][i]) q.push(ch[0][i]);while (!q.empty()){int now=q.front(); q.pop();for (i=0;i<26;i++){if (!ch[now][i]){ch[now][i]=ch[fail[now]][i];continue;}int tmp=ch[now][i];fail[tmp]=ch[fail[now]][i];q.push(tmp);}}}void ac(){int i;int l=strlen(ss),now=0,ans=0;for (i=0;i<l;i++){visit[now]=1;int x=ss[i]-'a';int y=ch[now][x];while (y && !visit[y]) {visit[y]=true;ans+=is_end[y];y=fail[y];}now=ch[now][x];}    printf("%d\n",ans); }int main(){int i,t,n;scanf("%d",&t);while (t--){tot=0;memset(ch,0,sizeof(ch));memset(visit,0,sizeof(visit));memset(is_end,0,sizeof(is_end));        memset(fail,0,sizeof(fail));scanf("%d",&n);    for (i=1;i<=n;i++)    {    scanf("%s",&st);    trie();}    sp();scanf("%s",&ss);ac();  }}

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