AC自动机 模板

AC自动机模板

#include <bits/stdc++.h>

using namespace std;
const int maxn = 1e6 + 500;
const int inf = 1e9;

int minv[maxn] , n ;
char base[maxn] , str[maxn];

struct AC_Auto{
    const static int LetterSize = 26;
	const static int TrieSize = 26 * ( 1e5 + 50); 
	int tot;
	int fail[TrieSize]; 
	int suffixlink[TrieSize]; 

	struct node{
		int ptr[LetterSize];
		int val;
	}tree[TrieSize];

	inline int GetLetterIdx(char c){
		return c - 'a';
	}

	void init_node(node & s){
		memset( s.ptr , 0 , sizeof( s.ptr ) );
		s.val = 0;
	}

	void find(const char * str){
		int len = strlen( str );
		int j = 0;
		for(int i = 0 ; i < len ; ++ i){
			int idx = GetLetterIdx( str[i] );
			while(j && !tree[j].ptr[idx]) j = fail[j];
			j = tree[j].ptr[idx];
			if(suffixlink[j]) minv[i] = suffixlink[j];
			else minv[i] = 0;
		}
	}

	void insert(const char * str){
		int len = strlen( str );
		int cur = 0;
		for(int i = 0 ; i < len ; ++ i){
			int idx = GetLetterIdx( str[i] );
			if(!tree[cur].ptr[idx]){
				tree[cur].ptr[idx] = tot;
				init_node( tree[tot++] );
			}
			cur = tree[cur].ptr[idx];
		}
		if(tree[cur].val == 0) tree[cur].val = len;
		else tree[cur].val = min( tree[cur].val , len );
	}

	void build_fail(){
		queue < int > Q; // 开在栈中 , 如果节点数较多 , 可设为全局变量
		suffixlink[0] = fail[0] = 0;
		for(int i = 0 ; i < LetterSize ; ++ i)
			if(tree[0].ptr[i]){
				int index = tree[0].ptr[i];
				fail[index] = 0 , suffixlink[index] = tree[index].val;
				Q.push( index );
			}
		while(!Q.empty()){
			int x = Q.front() ; Q.pop();
			for(int i = 0 ; i < LetterSize ; ++ i)
				if(tree[x].ptr[i]){
					int v = tree[x].ptr[i];
					int j = fail[x];
					while( j && !tree[j].ptr[i] ) j = fail[j];
					fail[v] = tree[j].ptr[i];
					suffixlink[v] = suffixlink[fail[v]];
					if(suffixlink[v] == 0){
						if(suffixlink[x]) suffixlink[v] = suffixlink[x] + 1;
					}
					else if(suffixlink[x]) suffixlink[v] = min( suffixlink[v] , suffixlink[x] + 1 );
					if(tree[v].val){
						if(suffixlink[v]==0) suffixlink[v] = tree[v].val;
						else suffixlink[v] = min( suffixlink[v] , tree[v].val );
					}
					Q.push( v );
				}
		}
	}

	void init(){ tot = 1 ; init_node( tree[0] );}

}ac_auto;

int main(int argc,char *argv[]){
	int Case , cas = 1;
	scanf("%d" , &Case);
	while(Case--){
		scanf("%s%d",base,&n);
		ac_auto.init();
		for(int i = 0 ; i < n ; ++ i){
			scanf("%s" , str);
			ac_auto.insert( str );
		}
		ac_auto.build_fail();
		ac_auto.find( base );
		int len = strlen( base );
		long long ans = 0 ;
		int last = 0;
		for(int i = 0 ; i < len ; ++ i){
			if(minv[i] == 0) ans += ( i - last + 1 );
			else ans += minv[i] - 1 , last = max( last , i + 2 - minv[i] );
		}
		printf("Case #%d: %lld
" , cas++ , ans );
	}
	return 0;
}
原文地址:https://www.cnblogs.com/qscqesze/p/5582672.html