hdu2222-AC自动机

Orz  Kuangbin和昀牛--

 

 

#include <iostream> #include <cstdlib> #include <cstring> #include <cstdio> #include <algorithm> #include <queue> using namespace std; #define INF 1<<29 #define eps 1e-8 #define A system("pause") #define rep(i,h,n) for(int i=(h);i<(n);i++) #define ms(a,b) memset((a),(b),sizeof(a)) const int maxn=500000+10; struct AC_machine {        int next[maxn][26],fail[maxn],end[maxn];        int root,L;        inline int newnode()        {             rep(i,0,26)                  next[L][i]=-1;             end[L++]=0;             return L-1;        }        inline void init()        {             L=0;             root=newnode();        }        inline void  insert(char str[])        {             int len=strlen(str);             int now=root;             rep(i,0,len)             {                  if(next[now][str[i]-'a']==-1)//当前结点不存在，新建结点；                      next[now][str[i]-'a']=newnode();                  now=next[now][str[i]-'a'];//指向该结点;             }             end[now]++;        }        inline void build_AC()//BFS构建AC自动机的过程；        {              queue<int>q;              fail[root]=root;//根节点的失败指针指向自己；              rep(i,0,26)              {                   if(next[root][i]==-1)                       next[root][i]=root;                   else                   {                       fail[next[root][i]]=root;                       q.push(next[root][i]);                   }              }              while(!q.empty())              {                   int now=q.front();                   q.pop();                   rep(i,0,26)                   {                        if(next[now][i]==-1)                             next[now][i]=next[fail[now]][i];                        else                        {                             fail[next[now][i]]=next[fail[now]][i];                             q.push(next[now][i]);                        }                   }              }        }        inline int match(char str[])        {               int len=strlen(str);               int now=root;               int res=0;               rep(i,0,len)               {                    now=next[now][str[i]-'a'];                    int temp=now;                    while(temp!=root)                    {                         res+=end[temp];                         end[temp]=0;                         temp=fail[temp];                    }               }               return res;        }        inline void debug()        {             for(int i = 0;i < L;i++)             {                 printf("id = %3d,fail = %3d,end = %3d,chi = [",i,fail[i],end[i]);                 for(int j = 0;j < 26;j++)                     printf("%2d",next[i][j]);                     printf("]\n");             }        } }AC; char str[maxn<<1]; int test,n; int main() {     scanf("%d",&test);     while(test--)     {          scanf("%d",&n);          AC.init();          rep(i,0,n)          {               scanf("%s",str);               AC.insert(str);          }          //AC.debug();          AC.build_AC();          scanf("%s",str);          printf("%d\n",AC.match(str));     }     //A;     return 0; }

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