点击打开链接题目链接
Keywords Search Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 42838 Accepted Submission(s): 13488
Wiskey also wants to bring this feature to his image retrieval system.
Every image have a long description, when users type some keywords to find the image, the system will match the keywords with description of image and show the image which the most keywords be matched.
To simplify the problem, giving you a description of image, and some keywords, you should tell me how many keywords will be match.
Each case will contain two integers N means the number of keywords and N keywords follow. (N <= 10000)
Each keyword will only contains characters 'a'-'z', and the length will be not longer than 50.
The last line is the description, and the length will be not longer than 1000000.
ac自己主动机模板题
代码:
#include<cstdio> #include<cstring> #include<algorithm> #include<queue> using namespace std; char str1[55],str2[1111111]; struct node{ node *fail,*next[26]; int ed; node(){ ed=0; fail=NULL; for(int i=0;i<26;i++) next[i]=NULL; } }*q[511111],*root; void tree_insert(char *str){ node *p=root; int l=strlen(str); int id; for(int i=0;i<l;i++){ id=str[i]-'a'; if(p->next[id]==NULL){ p->next[id]=new node(); } p=p->next[id]; } p->ed++; } void build_ac_automachine(){ int i; node *temp,*p; root->fail=NULL; int fr,ed; fr=ed=0; q[ed++]=root; while(fr<ed){ temp=q[fr++]; for(i=0;i<26;i++){ if(temp->next[i]!=NULL){ if(temp==root) temp->next[i]->fail=root; else { p=temp->fail; while(p){ if(p->next[i]){ temp->next[i]->fail=p->next[i]; break; } p=p->fail; } if(p==NULL) temp->next[i]->fail=root; } q[ed++]=temp->next[i]; } } } } int query(char *str){ int cnt=0; int l=strlen(str); node *p=root; for(int i=0;i<l;i++){ int id=str[i]-'a'; while(p->next[id]==NULL&&p!=root) p=p->fail; p=p->next[id]; if(p==NULL) p=root; node *temp=p; while(temp!=root&&temp->ed!=-1){ cnt+=temp->ed; temp->ed=-1; temp=temp->fail; } } return cnt; } int main(){ int t,n; scanf("%d",&t); while(t--){ root=new node(); scanf("%d",&n); while(n--){ scanf("%s",str1); tree_insert(str1); } scanf("%s",str2); build_ac_automachine(); printf("%d\n",query(str2)); } return 0; }