模板汇总——AC自动机

　

AC自动机 模板题 HDU-2222 Keywords Search

 #include<bits/stdc++.h>
 using namespace std;
 #define LL long long
 #define ULL unsigned LL
 #define fi first
 #define se second
 #define lson l,m,rt<<1
 #define rson m+1,r,rt<<1|1
 #define max3(a,b,c) max(a,max(b,c))
 #define min3(a,b,c) min(a,min(b,c))
 const int INF = 0x3f3f3f3f;
 const LL mod = 1e9+;
 typedef pair<int,int> pll;
 const int N = 1e5+, M = 1e3;
 char str[N*];
 int trie[N*][];
 int fair[N*];
 int cnt[N*];
 int tot = ;
 void Insert(){
     int rt = , len = strlen(str);
     for(int i = ; i < len; i++){
         int id = str[i] - 'a';
         if(trie[rt][id] == ){
             cnt[tot] = ;
             fair[tot] = ;
             trie[rt][id] = tot++;
         }
         rt = trie[rt][id];
     }
     cnt[rt]++;
 }
 void Build_tree(){
     queue<int> q;
     q.push();
     int p;
     while(!q.empty()){
         int tmp = q.front();
         q.pop();
         for(int i = ; i < ; i++){
             if(trie[tmp][i] != ){
                 if(tmp == )
                     fair[trie[tmp][i]] = ;
                 else{
                     p = fair[tmp];
                     while(p){
                         if(trie[p][i]){
                             fair[trie[tmp][i]] = trie[p][i];
                             break;
                         }
                         else p = fair[p];
                     }
                     if(!p)  fair[trie[tmp][i]] = ;
                 }
                 q.push(trie[tmp][i]);
             }
         }
     }
 }
 int Query(){
     int rt = , ret = , len = strlen(str);
     for(int i = ; i < len; i++){
         int id = str[i] - 'a';
         while(!trie[rt][id] && rt != ) rt = fair[rt];
         rt = trie[rt][id];
         if(rt == ) rt = ;
         int tmp = rt;
         while(tmp != ){
             if(cnt[tmp] >= ){
                 ret += cnt[tmp];
                 cnt[tmp] = -;
             }
             else break;
             tmp = fair[tmp];
         }
     }
     return ret;
 }
 void init(){
     for(int i = ; i < tot; i++){
         for(int j = ; j < ; j++)
             trie[i][j] = ;
     }
     tot = ;
 }
 int main(){
     int T;
     scanf("%d", &T);
     while(T--){
         init();
         int n;
         scanf("%d", &n);
         while(n--){
             scanf("%s", str);
             Insert();
         }
         Build_tree();
         scanf("%s", str);
         printf("%d\n", Query());
     }
     return ;
 }

2进制分组AC自动机

String Set Queries

假如给你21个串： 分为 16+4+1，再添加一个串的时候，即21+1， 22 = 16+4+1+1 = 16 + 4 + 2。 这样每次加串之后只会有logn个操作，查询也变成logn操作， 对于同一个串建立fair指针的次数就少了。

 #include<bits/stdc++.h>
 using namespace std;
 #define Fopen freopen("_in.txt","r",stdin); freopen("_out.txt","w",stdout);
 #define LL long long
 #define ULL unsigned LL
 #define fi first
 #define se second
 #define pb push_back
 #define lson l,m,rt<<1
 #define rson m+1,r,rt<<1|1
 #define max3(a,b,c) max(a,max(b,c))
 #define min3(a,b,c) min(a,min(b,c))
 typedef pair<int,int> pll;
 const int INF = 0x3f3f3f3f;
 const LL mod =  (int)1e9+;
 const int N = 3e5 + ;
 struct Node{
     static const int m = ;static const int KN = N;
     int next[KN][m], fair[KN], tot = , mark[KN], mark1[KN], root[], cnt = , si[];
     void Build(int x){
         queue<int> q;
         q.push(x);
         int pos, p, v;
         while(!q.empty()){
             pos = q.front(), q.pop();
             for(int i = ; i < m; i++){
                 if(!next[pos][i]) continue;
                 p = fair[pos]; v = next[pos][i];
                 while(p && !next[p][i]) p = fair[p];
                 if(p) fair[v] = next[p][i];
                 else fair[v] = x;
                 q.push(v);
                 mark1[v] = mark1[fair[v]] + mark[v];
             }
         }
     }
     void Add(char s[], char ch){
         root[++cnt] = ++tot; si[cnt] = ;
         int pos = root[cnt];
         for(int i = ; s[i]; i++){
             if(!next[pos][s[i]-ch]) next[pos][s[i]-ch] = ++tot;
             pos = next[pos][s[i]-ch];
         }
         mark[pos]++;
         while(si[cnt] == si[cnt-]){
             Unit(root[cnt-], root[cnt]);
             si[--cnt] *= ;
         }
         Build(root[cnt]);
     }
     int Query(char s[], char ch){
         int pos, ret = ;
         for(int id = ; id <= cnt; id++){
             pos = root[id];
             for(int i = ; s[i]; i++){
                 while(pos && !next[pos][s[i]-ch]) pos = fair[pos];
                 if(pos) pos = next[pos][s[i]-ch];
                 else pos = root[id];
                 ret += mark1[pos];
             }
         }
         return ret;
     }
     void Unit(int u, int v){
         mark[u] += mark[v];
         for(int i = ; i < m; i++){
             if(!next[u][i] || !next[v][i]) next[u][i] += next[v][i];
             else Unit(next[u][i], next[v][i]);
         }
     }
 }ac[];
 char str[N];
 int main(){
     int n, k;
     scanf("%d", &n);
     while(n--){
         scanf("%d%s", &k, str);
         if(k <= ) ac[k-].Add(str, 'a');
         else {
             printf("%d\n", ac[].Query(str, 'a')-ac[].Query(str, 'a'));
             fflush(stdout);
         }
     }
     return ;
 }

 AC自动机