AC自动机 HDOJ 2222 Keywords Search

  1 /*
  2     题意：每个文本串的出现次数
  3     AC自动机：入门题，注意关键词重复和出现过的关键词的次数不算到总数内    
  4 */
  5 /************************************************
  6 * Author        :Running_Time
  7 * Created Time  :2015-8-14 14:14:32
  8 * File Name     :AC.cpp
  9  ************************************************/
 10 
 11 #include <cstdio>
 12 #include <algorithm>
 13 #include <iostream>
 14 #include <sstream>
 15 #include <cstring>
 16 #include <cmath>
 17 #include <string>
 18 #include <vector>
 19 #include <queue>
 20 #include <deque>
 21 #include <stack>
 22 #include <list>
 23 #include <map>
 24 #include <set>
 25 #include <bitset>
 26 #include <cstdlib>
 27 #include <ctime>
 28 using namespace std;
 29 
 30 #define lson l, mid, rt << 1
 31 #define rson mid + 1, r, rt << 1 | 1
 32 typedef long long ll;
 33 const int MAXN = 1e4 + 10;
 34 const int MAXNODE = MAXN * 50 + 10;
 35 const int INF = 0x3f3f3f3f;
 36 const int SIGMA_SIZE = 26;
 37 const int MOD = 1e9 + 7;
 38 struct AC   {
 39     int ch[MAXNODE][SIGMA_SIZE], f[MAXNODE], sz;
 40     int val[MAXNODE];
 41     void init(void)   { 
 42         memset (ch[0], 0, sizeof (ch[0]));
 43         sz = 1; val[0] = 0;
 44     }
 45     int idx(char c) {
 46         return c - ‘a‘;
 47     }
 48     void insert(char *s) {
 49         int u = 0;
 50         for (int i=0; s[i]; ++i)   {
 51             int c = idx (s[i]);
 52             if (!ch[u][c])  {
 53                 memset (ch[sz], 0, sizeof (ch[sz]));
 54                 val[sz] = 0;
 55                 ch[u][c] = sz++;
 56             }
 57             u = ch[u][c];
 58         }
 59         val[u]++;
 60     }
 61     void build(void)    {
 62         queue<int> Q;   f[0] = 0;
 63         for (int i=0; i<SIGMA_SIZE; ++i)    {
 64             int u = ch[0][i];
 65             if (u)  {
 66                 f[u] = 0;   Q.push (u);
 67             }
 68             else    ch[0][i] = 0;
 69         }
 70         while (!Q.empty ()) {
 71             int u = Q.front (); Q.pop ();
 72             for (int i=0; i<SIGMA_SIZE; ++i)  {
 73                 int &v = ch[u][i];
 74                 if (!v) {
 75                     v = ch[f[u]][i];    continue;
 76                 }
 77                 Q.push (v);
 78                 f[v] = ch[f[u]][i];
 79             }
 80         }
 81     }
 82     int query(char *T)  {
 83         int ret = 0; int j = 0;
 84         for (int i=0; T[i]; ++i)   {
 85             int c = idx (T[i]);
 86             j = ch[j][c];
 87             int u = j;
 88             while (u)   {
 89                 ret += val[u];  val[u] = 0;
 90                 u = f[u];
 91             }
 92         }
 93         return ret;
 94     }
 95 }ac;
 96 char p[55], t[1000010];
 97 
 98 int main(void)    {     //HDOJ 2222 Keywords Search
 99     int T;  scanf ("%d", &T);
100     while (T--) {
101         int n;   scanf ("%d", &n);
102         ac.init ();
103         for (int i=1; i<=n; ++i)    {
104             scanf ("%s", p);    ac.insert (p);
105         }
106         ac.build ();    scanf ("%s", t);
107         printf ("%d\n", ac.query (t));
108     }
109 
110     return 0;
111 }