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hdu 4787 GRE Words Revenge 在线AC自动机

 

hdu 4787

GRE Words Revenge

Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 327680/327680 K (Java/Others)
Total Submission(s): 2505    Accepted Submission(s): 614


Problem Description
  Now Coach Pang is preparing for the Graduate Record Examinations as George did in 2011. At each day, Coach Pang can:
  "+w": learn a word w
  "?p": read a paragraph p, and count the number of learnt words. Formally speaking, count the number of substrings of p which is a learnt words.
  Given the records of N days, help Coach Pang to find the count. For convenience, the characters occured in the words and paragraphs are only ‘0‘ and ‘1‘.
 

 

Input
  The first line of the input file contains an integer T, which denotes the number of test cases. T test cases follow.
  The first line of each test case contains an integer N (1 <= N <= 105), which is the number of days. Each of the following N lines contains either "+w" or "?p". Both p and w are 01-string in this problem.
  Note that the input file has been encrypted. For each string occured, let L be the result of last "?" operation. The string given to you has been shifted L times (the shifted version of string s1s2 ... sk is sks1s2 ... sk-1). You should decrypt the string to the original one before you process it. Note that L equals to 0 at the beginning of each test case.
  The test data guarantees that for each test case, total length of the words does not exceed 105 and total length of the paragraphs does not exceed 5 * 106.
 

 

Output
  For each test case, first output a line "Case #x:", where x is the case number (starting from 1).
  And for each "?" operation, output a line containing the result.
 

 

Sample Input
2 3 +01 +01 ?01001 3 +01 ?010 ?011
 

 

Sample Output
Case #1: 2 Case #2: 1 0
 

 

Source
2013 Asia Chengdu Regional Contest
 

 

可持久化,也就是可以在线,边询问边插入模式串,如果暴力每次插入后重建ac自动机,那么复杂度就是O(N*N),,可以想到用分块(dalao是这么叫的);建立一个大的自动机,一个小的自动机,小的自动机规模是sqrt(N),大的是N,每次插入时在小的buf 里添加字串,重构自动机,buf的规模超过sqrt(N),合并到大的自动机里大的重建,复杂度为O(sqrt(N) * N);合并就是buf ac 的字典树一起跑,如果ac里没有buf 的结点,就新建,然后权值|=buf.val[],(有节点也要| =,因为原来的不一定是单词,但现在是了);

 

 

  1 //2017-07-15 19:28:18
  2 //2017-07-15 20:10:10 
  3 #include<algorithm>
  4 #include<iostream>
  5 #include<cstdlib>
  6 #include<cstdio>
  7 #include<cmath>
  8 #include<map>
  9 #include"set"
 10 #include"queue"
 11 #include"vector"
 12 #include"iomanip"
 13 #include"cstring"
 14 #define inf 1<<29
 15 #define ll long long
 16 #define re register
 17 #define il inline
 18 #define rep(i,a,b) for(register int i=a;i<=b;++i)
 19 #define file(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout);
 20 using namespace std;
 21 const int N=100010;
 22 char tmp[5000100],s[5000100];
 23 struct ACAutomation{
 24     int f[N],ch[N][2],lst[N],sz;
 25     int val[N];
 26     il void init() {
 27         sz=0;ch[0][0]=ch[0][1]=0;lst[0]=0;
 28         //val[0]=0;
 29     }
 30     il int newnode(){
 31         ++sz;
 32         ch[sz][0]=ch[sz][1]=f[sz]=lst[sz]=0;
 33         val[sz]=0;//
 34         return sz;
 35     }
 36     il bool search(char *s,int len) {
 37         re int t=0,c;
 38         for(re int i=0;i<len;++i){
 39             c=s[i]-0;
 40             if(!ch[t][c])
 41                 return 0;
 42             t=ch[t][c];
 43         }
 44         return val[t];
 45     }
 46     il void insert(char *s,int len){
 47         re int t=0,c;
 48         for(re int i=0;i<len;++i){
 49             c=s[i]-0;
 50             if(!ch[t][c])
 51                 ch[t][c]=newnode();
 52             t=ch[t][c];
 53         }
 54         val[t]=1;
 55     }
 56     il void build() {
 57         queue<int> q;
 58         for(re int i=0;i<2;++i){
 59             if(ch[0][i])
 60                 q.push(ch[0][i]),f[ch[0][i]]=0,lst[ch[0][i]]=0;
 61         }
 62         re int r,v,u;
 63         while(!q.empty()) {
 64             r=q.front();q.pop();
 65             for(re int c=0;c<2;++c) {
 66                 u=ch[r][c];
 67                 if(!u) continue;
 68                 q.push(u);
 69                 v=f[r];
 70                 while(v&&!ch[v][c]) v=f[v];
 71                 f[u]=ch[v][c];
 72                 lst[u] = val[f[u]] ? f[u] : lst[f[u]];
 73             }
 74         }
 75     }
 76     il int run(char *s,int len) {
 77         re int t=0,ans=0,c;
 78         for(re int i=0;i<len;++i) {
 79             c=s[i]-0;
 80             while(t&&!ch[t][c]) t=f[t];
 81             t=ch[t][c];
 82             for(re int p=t;p;p=lst[p])
 83                 ans+=val[p];
 84         }
 85         return ans;
 86     }
 87 };
 88 ACAutomation ac,buf;
 89 
 90 inline int gi() {
 91     re int res=0,f=1;re char ch=getchar();
 92     while((ch<0||ch>9)&&ch!=-) ch=getchar();
 93     if(ch==-) f=-1,ch=getchar();
 94     while(ch>=0&&ch<=9) res=res*10+ch-0,ch=getchar();
 95     return res*f;
 96 }
 97 il void bfs() {
 98     queue<int> U,V;
 99     U.push(0),V.push(0);
100     re int u,v,r1,r2;
101     while(!U.empty()) {
102         u=U.front(),v=V.front();
103         U.pop(),V.pop();
104         for(re int c=0;c<2;++c)
105             if(buf.ch[u][c]) {
106                 r1=buf.ch[u][c],r2=ac.ch[v][c];
107                 if(!r2) {
108                     ac.ch[v][c]=ac.newnode();
109                 }
110                 r2=ac.ch[v][c];
111                 ac.val[r2]|=buf.val[r1];
112                 U.push(r1),V.push(r2);
113             }
114     }
115 }
116 il void go() {
117     bfs();
118     buf.init();
119     ac.build();    
120 }
121 int main(){
122     file("Y");
123     re int cas=gi();
124     rep(tt,1,cas) {
125         printf("Case #%d:\n",tt);
126         ac.init();
127         buf.init();
128         re int n=gi();
129         re int l=0;
130         rep(qyp,1,n) {
131             scanf("%s",tmp);
132             re int len=strlen(tmp);
133             re int p=l%(len-1);
134             s[0]=tmp[0];
135             for(re int i=1;i<=p;i++) s[i+len-1-p]=tmp[i];
136             for(re int i=1;i<len-p;++i) s[i]=tmp[i+p];
137             if(s[0]==+) {
138                 if(buf.search(s+1,len-1)||ac.search(s+1,len-1)) continue;
139                 buf.insert(s+1,len-1);
140                 buf.build();
141                 if(buf.sz>333) go();
142             }
143             else {
144                 l=ac.run(s+1,len-1) + buf.run(s+1,len-1);
145                 printf("%d\n",l);
146             }
147         }
148     }
149     return 0;
150 }

 

hdu 4787 GRE Words Revenge 在线AC自动机