AC 自动机 洛谷P3808 P3796 P5357

洛谷P3808

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5;
int ch[maxn][30], fa[maxn], End[maxn];
int cnt = 0 , n;
int get_num(char c){return c - 'a';}
void build(string s){
	int cur = 0, len = s.length();
	for(int i = 0; i < len; i++){
		int c = get_num(s[i]);
		if(!ch[cur][c]) ch[cur][c] = ++cnt;
		cur = ch[cur][c];
	}
	End[cur]++;
}
void get_fail(){
	queue<int> q;
	for(int i = 0; i < 26; i++)
		if(ch[0][i])q.push(ch[0][i]);		
	while(!q.empty()){
		int u = q.front();	q.pop();
		for(int i = 0; i < 26; i++){
			int &v = ch[u][i];
			if(v){
				fa[v] =ch[fa[u]][i];
				q.push(v);
			}else v = ch[fa[u]][i];
		}		
	}
}
int query(string s){
	int cur = 0, ans = 0, len = s.length();
	for(int i = 0; i < len; i++){
		int c = get_num(s[i]);
		cur = ch[cur][c];
		for(int j = cur; j && End[j] != -1; j = fa[j]){
			ans += End[j];	End[j] = -1;
		}	
	}
	return ans;
}
int main() { 
	string s;
	cin >> n;
	for(int i = 0; i < n; i++){cin >> s; build(s);}
	get_fail();		cin >> s;
	cout << query(s) << endl;	
    return 0;
}

洛谷P3796

#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5;
int ch[maxn][30], fa[maxn], End[maxn], ans[158], Maxs;
int cnt = 0 , n;
string str[158];
int get_num(char c){return c - 'a';}
void build(string s, int x){
	int cur = 0, len = s.length();
	for(int i = 0; i < len; i++){
		int c = get_num(s[i]);
		if(!ch[cur][c]) ch[cur][c] = ++cnt;
		cur = ch[cur][c];
	}
	End[cur] = x;
}
void get_fail(){
	queue<int> q;
	for(int i = 0; i < 26; i++)
		if(ch[0][i])q.push(ch[0][i]);		
	while(!q.empty()){
		int u = q.front();	q.pop();
		for(int i = 0; i < 26; i++){
			int &v = ch[u][i];
			if(v){
				fa[v] =ch[fa[u]][i];
				q.push(v);
			}else v = ch[fa[u]][i];
		}		
	}
}
void query(string s){
	int cur = 0, len = s.length();
	for(int i = 0; i < len; i++){
		int c = get_num(s[i]);
		cur = ch[cur][c];
		for(int j = cur; j; j = fa[j])
			if(End[j]){
				ans[End[j]]++; 
				Maxs = max(Maxs, ans[End[j]]);
		}
	}	
}
int main() {
	string s; 	
	while(cin >> n && n){		
		for(int i = 0; i <= cnt; i++){			
			for(int j = 0; j < 26; j++)ch[i][j] = 0;
			fa[i] = 0; 
			End[i] = 0;
		}
		memset(ans, 0, sizeof(ans));		
		Maxs = 0;
		cnt = 0;
		for(int i = 1; i <= n; i++){
			cin >> str[i]; build(str[i], i);
		}
		get_fail();		cin >> s;
		query(s);
		cout << Maxs << endl;	
		for(int i = 1; i <= n; i++)
			if(ans[i] == Maxs)cout << str[i] << endl;
	}	
    return 0;
}

luogu p5357

#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e6 + 6, maxm = 2e5 + 6;
int ch[maxn][30], fa[maxn], End[maxn], ans[maxm], Map[maxn], In[maxn];
int cnt = 0 , n;
int pos[maxn];
int get_num(char c){return c - 'a';}
void build(string s, int x){
	int cur = 0, len = s.length();
	for(int i = 0; i < len; i++){
		int c = get_num(s[i]);
		if(!ch[cur][c]) ch[cur][c] = ++cnt;
		cur = ch[cur][c];
	}	
//	if(!End[cur])End[cur] = x;
//	Map[x] = End[cur];    
	pos[x] = cur;	//new
}
void get_fail(){
	queue<int> q;
	for(int i = 0; i < 26; i++)
		if(ch[0][i])q.push(ch[0][i]);		
	while(!q.empty()){
		int u = q.front();	q.pop();
		for(int i = 0; i < 26; i++){
			int &v = ch[u][i];
			if(v){
				fa[v] =ch[fa[u]][i];	
				In[ch[fa[u]][i]]++ ; //新加
				q.push(v);
			}else v = ch[fa[u]][i];
		}		
	}
}
void query(string s){
	int cur = 0, len = s.length();
	for(int i = 0; i < len; i++){
		int c = get_num(s[i]);
		cur = ch[cur][c];
//		for(int j = cur; j; j = fa[j])
//			if(End[j])ans[End[j]]++; 
		ans[cur]++; 	//替换						
	}	
}
void topu(){
	queue<int> q;
    for(int i=1;i<=cnt;i++)
    	if(In[i]==0)q.push(i);
    while(!q.empty()){
        int u=q.front();	q.pop();
        int v=fa[u];	In[v]--;
        	ans[v] += ans[u];
        if(In[v]==0)q.push(v);
    }
}
int main() {
	string s; 	
	cin >> n;		
	for(int i = 1; i <= n; i++){
		cin >> s; build(s, i);
	}
	get_fail();		cin >> s;
	query(s);	
	topu();
	for(int i = 1; i <= n; i++)
		cout << ans[pos[i]] << endl;	
    return 0;
}