AC自动机总结 part1

这回总结的基本都是模板题……

Hdu 2896 病毒侵袭

用set统计哪些子串出现过。注意字符集并不只有a-z

#pragma warning(disable:4786)#include <set>#include <map>#include <cmath>#include <queue>#include <stack>#include <string>#include <vector>#include <cstdio>#include <cstdlib>#include <cstring>#include <sstream>#include <iostream>#include <algorithm>using namespace std;const int MAXPT=500007;   //最大节点数const int size=100;     //子节点数const char start=32;  //子节点标号对应关系set<int>iSet[1007]; class Ac_Automat{private:struct Node{Node *fail;Node *next[size];int cnt;    //各种用途bool flag;   //是否为单词结束void newnode () //生成节点{fail=NULL;for (int i=0;i<size;i++)next[i]=NULL;cnt=0;flag=false;}};Node *q[MAXPT],H[MAXPT],*root;int fr,tl,t;public:    void Init (){fr = tl = 0;t = 0;H[t].newnode();root = &H[t++];}void Insert (char *s,int id){int len = strlen(s);Node *p = root;for (int i=0;i<len;i++){int k = s[i] - start;            if (p->next[k] == NULL)            {H[t].newnode();p->next[k] = &H[t++];}p = p->next[k];}p->cnt=id;p->flag=true;}    void Build (){root->fail = NULL;q[tl] = root;while (fr <= tl){Node *tmp = q[fr++];Node *p = NULL;for (int i=0;i<size;i++) if (tmp->next[i]){if (tmp == root)tmp->next[i]->fail = root;else{p = tmp->fail;while (p != NULL){if (p->next[i]){tmp->next[i]->fail = p->next[i];break;}p = p->fail;}if (p == NULL) tmp->next[i]->fail = root;}q[++tl] = tmp->next[i];}}}void Query (char *s,int id){Node *p = root;int len = strlen(s);for (int i=0;i<len;i++){int k = s[i] - start;while (p->next[k] == NULL && p != root)p = p->fail;p = p->next[k];if (p == NULL) p = root;Node *tmp = p;while (tmp != root){if (tmp->cnt != 0)iSet[id].insert(tmp->cnt);tmp = tmp->fail;}}}}ac;char s1[202],s2[10007]; int main (){#ifdef ONLINE_JUDGE#elsefreopen("read.txt","r",stdin);#endifint i,m,n;while (~scanf("%d",&n)){ac.Init();for (i=0;i<=1000;i++)iSet[i].clear();for (i=1;i<=n;i++){scanf("%s",s1);ac.Insert(s1,i);}ac.Build();scanf("%d",&m);for (i=1;i<=m;i++){scanf("%s",s2);ac.Query(s2,i);}int tol = 0;set<int>::iterator it;for (i=1;i<=m;i++) if (iSet[i].size() >= 1){printf("web %d:",i);tol++;for (it=iSet[i].begin(); it!=iSet[i].end();it++)printf(" %d",*it);printf("\n");}printf("total: %d\n",tol);}return 0;}

Hdu 3065 病毒侵袭持续中

此题模板串无重复

思路：AC自动机统计模板串出现次数

#include <cstdio>#include <set>#include <cctype>#include <algorithm>#include <map>#include <cstring>#include <queue>using namespace std;const int MAXPT = 500007;  //MAXPT = StringNumber * StringLengthconst int size = 26;const char start='a';int num[155]; class ACAutomaton{private:int chd[MAXPT][size];int val[MAXPT];//记录题目给的关键数据int fail[MAXPT];//fail指针int Q[MAXPT];//队列,用于广度优先计算fail指针int ID[228];//字母对应的Iint sz;//已使用节点个数public:    void Set ()//初始化,计算字母对应的儿子ID,如:'a'->0 ... 'z'->25{fail[0]=0;for (int i=0;i<size;i++)ID[i+start] = i;}    void Init (){Set();memset(chd[0],0,sizeof(chd[0]));sz = 1;}    void Insert (char *a,int id){int p=0;for (; *a ; a++){int c = ID[*a];if (!chd[p][c]){memset(chd[sz] , 0 , sizeof(chd[sz]));val[sz]=0;chd[p][c] = sz++;}p = chd[p][c];}val[p]=id;}void Build (){int *s=Q, *e=Q,i;for (i=0;i<size;i++)if (chd[0][i]){fail[ chd[0][i] ] = 0;*e ++ = chd[0][i];            }while (s != e){int u = *s++;for (i=0;i<size;i++){int &v = chd[u][i];if (v){*e ++ = v;fail[v] = chd[ fail[u] ][i];}elsev = chd[ fail[u] ][i];}}}void Query (char *s){int p=0,k,ans=0;for (; *s; s++){k = ID[*s];while (!chd[p][k] && p!=0)p = fail[p];p = chd[p][k];int rt = p;while (rt != 0){if (val[rt] != 0)num[val[rt]]++;rt = fail[rt];}}}}ac;char str[1000005],s[155][75];int ans[155];int main (){#ifdef ONLINE_JUDGE#elsefreopen("read.txt","r",stdin);#endifint i,n;while (scanf("%d",&n),n){ac.Init();memset(num,0,sizeof(num));memset(ans,0,sizeof(ans));for (i=1;i<=n;i++)scanf("%s",s[i]),ac.Insert(s[i],i);scanf("%s",str);ac.Build();ac.Query(str);int cnt=0,len=-1;for (i=1;i<=n;i++){if (num[i]>len){cnt=0;ans[++cnt]=i;len=num[i];}else if (num[i]==len)ans[++cnt]=i;}printf("%d\n",len);for (i=1;i<=cnt;i++)printf("%s\n",s[ans[i]]);}return 0;}

Hdu 3695 Computer Virus on Planet Pandora

题意：给出一些病毒串以及一个大串s，若s包含一个病毒串或其反串，则我们说其包含该病毒串。问s包含了多少病毒串？

题意：将病毒串插入自动机。用s以及其反串跑一遍。

#include <cstdio>#include <cctype>#include <cstring>#include <algorithm>using namespace std;const int MAXPT=500007;   //最大节点数const int size=26;     //子节点数const char start='A';  //子节点标号对应关系 class Ac_Automat{private:struct Node{Node *fail;Node *next[size];int cnt;    //各种用途:计数,标号等void newnode () //生成节点{fail=NULL;for (int i=0;i<size;i++)next[i]=NULL;cnt=0;}};Node *q[MAXPT],H[MAXPT],*root;int fr,tl,t;public:void Init (){fr = tl = 0;t = 0;H[t].newnode();root = &H[t++];}void Insert (char *s){int len = strlen(s);Node *p = root;for (int i=0;i<len;i++){int k = s[i] - start;if (p->next[k] == NULL){H[t].newnode();p->next[k] = &H[t++];}p = p->next[k];}p->cnt++;}void Build (){root->fail = NULL;q[tl] = root;while (fr <= tl){Node *tmp = q[fr++];Node *p = NULL;for (int i=0;i<size;i++) if (tmp->next[i]){if (tmp == root)tmp->next[i]->fail = root;else{p = tmp->fail;while (p != NULL){if (p->next[i]){tmp->next[i]->fail = p->next[i];break;}p = p->fail;}if (p == NULL) tmp->next[i]->fail = root;}q[++tl] = tmp->next[i];}}}int Query (char *s){int res = 0;Node *p = root;int len = strlen(s);for (int i=0;i<len;i++){int k = s[i] - start;while (p->next[k] == NULL && p != root)p = p->fail;p = p->next[k];if (p == NULL) p = root;Node *tmp = p;while (tmp != root && tmp->cnt != -1){res += tmp->cnt;tmp->cnt = - 1;tmp = tmp->fail;}}return res;}}ac;char str[5100000+10],s[5100000+10];void reverse (char *s){int len=strlen(s);int L=0,R=len-1;while (L<R)swap(s[L++],s[R--]);}void Deal (){int len=strlen(s),L=0;for (int i=0;i<len;i++){if (isupper(s[i]))str[L++]=s[i];else if (s[i]=='['){int k=0,j=i+1;while (isdigit(s[j])){k=k*10+s[j]-'0';j++;}i=j+1;for (int t=0;t<k;t++)str[L++]=s[j];}str[L]=0;}int ans=ac.Query(str);reverse(str);ans+=ac.Query(str);printf("%d\n",ans);}int main (){#ifdef ONLINE_JUDGE#elsefreopen("read.txt","r",stdin);#endifint T,n;scanf("%d",&T);while (T--){scanf("%d",&n);ac.Init();for (int i=1;i<=n;i++)scanf("%s",s),ac.Insert(s);ac.Build();scanf("%s",s);Deal ();}return 0;}

BZoj 3172: [Tjoi2013]单词

题目连接：http://61.187.179.132/JudgeOnline/problem.php?id=3172

ascll码表比a小1的字符是 ` ，用这个字符作为分割，将所有模式串连起来作为主串，用模式串构造自动机。然后就跟前面几道统计出现次数的题没有区别了。

注意会有重复的单词，我用了map映射来处理。

这个题貌似后缀数组也可以搞。

#pragma warning(disable:4786)#include <cstdio>#include <set>#include <cctype>#include <algorithm>#include <string>#include <map>#include <cstring>#include <queue>using namespace std;const int MAXPT = 4000007;  //MAXPT = StringNumber * StringLengthconst int size = 27;const char start='`';int num[205]; class ACAutomaton{private:int chd[MAXPT][size];int val[MAXPT];//记录题目给的关键数据int fail[MAXPT];//fail指针int Q[MAXPT];//队列,用于广度优先计算fail指针int ID[228];//字母对应的Iint sz;//已使用节点个数public:    void Set ()//初始化,计算字母对应的儿子ID,如:'a'->0 ... 'z'->25{fail[0]=0;for (int i=0;i<size;i++)ID[i+start] = i;}    void Init (){Set();memset(chd[0],0,sizeof(chd[0]));sz = 1;}    void Insert (char *a,int id){int p=0;for (; *a ; a++){int c = ID[*a];if (!chd[p][c]){memset(chd[sz] , 0 , sizeof(chd[sz]));val[sz]=0;chd[p][c] = sz++;}p = chd[p][c];}val[p]=id;}void Build (){int *s=Q, *e=Q,i;for (i=0;i<size;i++)if (chd[0][i]){fail[ chd[0][i] ] = 0;*e ++ = chd[0][i];            }while (s != e){int u = *s++;for (i=0;i<size;i++){int &v = chd[u][i];if (v){*e ++ = v;fail[v] = chd[ fail[u] ][i];}elsev = chd[ fail[u] ][i];}}}void Query (char *s){int p=0,k,ans=0;for (; *s; s++){k = ID[*s];while (!chd[p][k] && p!=0)p = fail[p];p = chd[p][k];int rt = p;while (rt != 0){if (val[rt] != 0)num[val[rt]]++;rt = fail[rt];}}}}ac;char str[100005*205],s[205][100005];int main (){#ifdef ONLINE_JUDGE#elsefreopen("read.txt","r",stdin);#endifint n,i;while (~scanf("%d",&n)){map<string,int> mp;ac.Init();memset(num,0,sizeof(num));memset(str,0,sizeof(str));    /// for (i=1;i<=n;i++){scanf("%s",s[i]);if (mp[s[i]]==0){mp[s[i]]=i;ac.Insert(s[i],i);}strcat(str,s[i]);strcat(str,"`");}ac.Build();ac.Query(str);for (i=1;i<=n;i++)printf("%d\n",num[mp[s[i]]]);}return 0;}

LightOJ 1427 Substring Frequency (II)

题目链接：http://lightoj.com/volume_showproblem.php?problem=1427

还是统计出现次数，有重复的单词。

#pragma warning(disable:4786)#include <cstdio>#include <set>#include <cctype>#include <algorithm>#include <string>#include <map>#include <cstring>#include <queue>using namespace std;const int MAXPT = 1000007;  //MAXPT = StringNumber * StringLengthconst int size = 26;const char start='a';int num[505]; class ACAutomaton{private:int chd[MAXPT][size];int val[MAXPT];//记录题目给的关键数据int fail[MAXPT];//fail指针int Q[MAXPT];//队列,用于广度优先计算fail指针int ID[228];//字母对应的Iint sz;//已使用节点个数public:    void Set ()//初始化,计算字母对应的儿子ID,如:'a'->0 ... 'z'->25{fail[0]=0;for (int i=0;i<size;i++)ID[i+start] = i;}    void Init (){Set();memset(chd[0],0,sizeof(chd[0]));sz = 1;}    void Insert (char *a,int id){int p=0;for (; *a ; a++){int c = ID[*a];if (!chd[p][c]){memset(chd[sz] , 0 , sizeof(chd[sz]));val[sz]=0;chd[p][c] = sz++;}p = chd[p][c];}val[p]=id;}void Build (){int *s=Q, *e=Q,i;for (i=0;i<size;i++)if (chd[0][i]){fail[ chd[0][i] ] = 0;*e ++ = chd[0][i];            }while (s != e){int u = *s++;for (i=0;i<size;i++){int &v = chd[u][i];if (v){*e ++ = v;fail[v] = chd[ fail[u] ][i];}elsev = chd[ fail[u] ][i];}}}void Query (char *s){int p=0,k,ans=0;for (; *s; s++){k = ID[*s];while (!chd[p][k] && p!=0)p = fail[p];p = chd[p][k];int rt = p;while (rt != 0){if (val[rt] != 0)num[val[rt]]++;rt = fail[rt];}}}}ac;char str[1000005],s[505][505];int main (){#ifdef ONLINE_JUDGE#elsefreopen("read.txt","r",stdin);#endifint T,n,i;scanf("%d",&T);for (int Cas=1;Cas<=T;Cas++){map <string,int> mp;printf("Case %d:\n",Cas);scanf("%d",&n);scanf("%s",str);ac.Init();memset(num,0,sizeof(num));for (i=1;i<=n;i++){scanf("%s",s[i]);if (mp[s[i]]==0){mp[s[i]]=i;ac.Insert(s[i],i);}}ac.Build();ac.Query(str);for (i=1;i<=n;i++)printf("%d\n",num[mp[s[i]]]);}return 0;}