[模板] - AC自动机 - 静态 - 感谢小太阳

#include<bits/stdc++.h>
using namespace std;
const int maxn = 300010;
const int dp_maxn = 1010;
const int INF = 0x3f3f3f3f;
const int type_N = 26;

int T, N, dp[dp_maxn][dp_maxn];
char in[60], text[1000010];
struct Trie
{
int nxt[maxn][type_N],
fail[maxn],
cnt[maxn],
size, root;
bool finish[maxn];

int newNode(){
for(int i = 0; i < type_N; ++ i)
nxt[size][i] = 0;
fail[size] = 0;
cnt[size] = 0;
finish[size] = false;
return size ++;
}
void init(){
size = 1;
root = newNode();
}
int idx(char ch){
/*if(ch == 'A')return 0;
if(ch == 'G')return 1;
if(ch == 'C')return 2;
return 3;*/
return ch - 'a';
}
void insert(char *s){
int now = root;
while(*s){
int index = idx(*s);
if(!nxt[now][index])
nxt[now][index] = newNode();
now = nxt[now][index];
++ s;
}
++ cnt[now];
finish[now] = true;
}
void build(){
queue<int> que;
fail[root] = root;
for(int i = 0; i < type_N; ++ i){
if(nxt[root][i]){
que.push(nxt[root][i]);
fail[nxt[root][i]] = root;
}
else nxt[root][i] = root;
}
while(que.size()){
int now = que.front();
que.pop();
finish[now] = finish[now] || finish[fail[now]];
for(int i = 0; i < type_N; ++ i){
if(nxt[now][i]){
que.push(nxt[now][i]);
fail[nxt[now][i]] = nxt[fail[now]][i];
}
else nxt[now][i] = nxt[fail[now]][i];
}
}
}
int Match(char *s){
int now = root, ans = 0;
while(*s){
int index = idx(*s);
while(now != root && nxt[now][index] == root){
//printf("now = %d\n", now);
now = fail[now];
}
now = nxt[now][index];
int match = now;
while(match != root){
//printf("match = %d, now = %d\n", match, now);
ans += cnt[match];
cnt[match] = 0;///查找匹配单词个数则加上这句；查找模板串出现次数则删掉这句
match = fail[match];
}
++ s;
}
return ans;
}
int meta(char *s){///type_N = 4,
int len = strlen(s);
memset(dp, 0x3f, sizeof(dp));
dp[0][root] = 0;
for(int i = 0; i < len; ++ i){
for(int j = 0; j < size; ++ j){
if(dp[i][j] < INF){
for(int k = 0; k < 4; ++ k){
int nstatus = nxt[j][k];
if(finish[nstatus])continue;
dp[i+1][nstatus] = min(dp[i+1][nstatus], dp[i][j] + (k != idx(s[i])));
}
}
}
}
int ans = INF;
for(int i = 0; i < size; ++ i)
ans = min(ans, dp[len][i]);
return ans == INF ? -1 : ans;
}
}ac;
int main(){
scanf("%d", &T);
while(T--){
ac.init();
scanf("%d", &N);
while(N--){
scanf("%s", in);
ac.insert(in);
}
ac.build();
scanf("%s", text);
printf("%d\n", ac.Match(text
4000
));
}
return 0;
}