AC Automaton
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AC Automaton
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// Problem: P3808 【模板】AC自動機(簡單版) // Contest: Luogu // URL: https://www.luogu.com.cn/problem/P3808 // Memory Limit: 512 MB // Time Limit: 1000 ms // // Powered by CP Editor (https://cpeditor.org)//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math") //#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt,tune=native") //#pragma GCC optimize(2) #include<cstdio> #include<iostream> #include<string> #include<cstring> #include<map> #include<cmath> #include<cctype> #include<vector> #include<set> #include<queue> #include<algorithm> #include<sstream> #include<ctime> #include<cstdlib> #include<random> #include<cassert> #define X first #define Y second #define L (u<<1) #define R (u<<1|1) #define pb push_back #define mk make_pair #define Mid ((tr[u].l+tr[u].r)>>1) #define Len(u) (tr[u].r-tr[u].l+1) #define random(a,b) ((a)+rand()%((b)-(a)+1)) #define db puts("---") using namespace std;//void rd_cre() { freopen("d://dp//data.txt","w",stdout); srand(time(NULL)); } //void rd_ac() { freopen("d://dp//data.txt","r",stdin); freopen("d://dp//AC.txt","w",stdout); } //void rd_wa() { freopen("d://dp//data.txt","r",stdin); freopen("d://dp//WA.txt","w",stdout); }typedef long long LL; typedef unsigned long long ULL; typedef pair<int,int> PII;const int N=5000010,mod=1e9+7,INF=0x3f3f3f3f; const double eps=1e-6;int n; int tr[N][26],idx,cnt[N]; int fail[N]; char s[N];int newnode() {int u=++idx; cnt[u]=0;for(int i=0;i<26;i++) tr[u][i]=0;return u; }void insert() {int n=strlen(s+1);int p=0;for(int i=1;i<=n;i++) {int u=s[i]-'a';if(!tr[p][u]) tr[p][u]=newnode();p=tr[p][u];}cnt[p]++; }void getfail() {queue<int>q;for(int i=0;i<26;i++) if(tr[0][i]) {fail[tr[0][i]]=0;q.push(tr[0][i]);}while(q.size()) {int u=q.front(); q.pop();for(int i=0;i<26;i++) {int p=tr[u][i];if(p) fail[p]=tr[fail[u]][i],q.push(p);else tr[u][i]=tr[fail[u]][i];}} }int query() {int ans=0;int n=strlen(s+1);int p=0;for(int i=1;i<=n;i++) {int u=tr[p][s[i]-'a'];while(u&&cnt[u]!=-1) {ans+=cnt[u]; cnt[u]=-1;u=fail[u];}p=tr[p][s[i]-'a'];}return ans; }int main() { // ios::sync_with_stdio(false); // cin.tie(0);idx=0; for(int i=0;i<26;i++) tr[0][i]=0;scanf("%d",&n);for(int i=1;i<=n;i++) {scanf("%s",s+1);insert();}getfail();scanf("%s",s+1);printf("%d\n",query());return 0; } /**/總結
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