zoukankan      html  css  js  c++  java
  • AC自动机 HDU2222 Keywords Search

    Keywords Search

    Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)
    Total Submission(s): 62674    Accepted Submission(s): 20749


    Problem Description
    In the modern time, Search engine came into the life of everybody like Google, Baidu, etc.
    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.
     
    Input
    First line will contain one integer means how many cases will follow by.
    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.
     
    Output
    Print how many keywords are contained in the description.
     
    Sample Input
    1 5 she he say shr her yasherhs
     
    Sample Output
    3
     
    Author
    Wiskey
     
     
    模板题,模板源自chaijing
     
     1 #include<iostream>
     2 #include<cstdio>
     3 #include<cstring>
     4 #include<algorithm>
     5 #include<queue>
     6 using namespace std;
     7 int t,n,num;
     8 int len,val,j;
     9 char s[1000010];
    10 struct data{
    11     int ch[30];
    12     int fail,cnt;//cnt 以该节点结束的词的个数 
    13 }tree[1000010];
    14 queue<int>q;
    15 void clear(int x){
    16     memset(tree[x].ch,0,sizeof(tree[x].ch));
    17     tree[x].fail=0;
    18     tree[x].cnt=0;
    19 }
    20 void trie(int x){
    21     len=strlen(s);
    22     for(int i=0;i<len;i++){
    23         val=s[i]-'a'+1;
    24         if(!tree[x].ch[val]){
    25             num++;
    26             clear(num);
    27             tree[x].ch[val]=num;
    28         }
    29         x=tree[x].ch[val];
    30     }
    31     tree[x].cnt++;
    32 }
    33 void build(){
    34     while(!q.empty()) q.pop();
    35     for(int i=1;i<=26;i++) 
    36         if(tree[0].ch[i]) q.push(tree[0].ch[i]);
    37     while(!q.empty()){
    38         int p=q.front();
    39         q.pop();
    40         for(int i=1;i<=26;i++){
    41             int fail=tree[p].fail;
    42             if(tree[p].ch[i]){
    43                 
    44                 tree[tree[p].ch[i]].fail=tree[fail].ch[i];
    45                 q.push(tree[p].ch[i]);
    46             }
    47             else tree[p].ch[i]=tree[fail].ch[i];
    48         }
    49     }
    50 }
    51 int find(int x){
    52     int ans=0;
    53     len=strlen(s);
    54     for(int i=0;i<len;i++){
    55         val=s[i]-'a'+1;
    56         while(x&&!tree[x].ch[val]) x=tree[x].fail;
    57         x=tree[x].ch[val];
    58         j=x;
    59         while(j&&tree[j].cnt!=-1){
    60             ans+=tree[j].cnt;
    61             tree[j].cnt=-1;
    62             j=tree[j].fail;
    63         }
    64     }
    65     return ans;
    66 }
    67 int main(){
    68     scanf("%d",&t);
    69     while(t){
    70         t--;
    71         num=0;
    72         clear(0);
    73         scanf("%d",&n);
    74         for(int i=1;i<=n;i++){
    75             scanf("%s",s);
    76             trie(0);
    77         }
    78         build();
    79         scanf("%s",s);
    80         printf("%d
    ",find(0));
    81     }
    82     return 0;
    83 }
     
     
  • 相关阅读:
    RabbitMQ安装(发生系统错误5。拒绝访问。发生系统错误1067。进程意外终止。)
    SQLServer执行脚本提示“系统找不到指定的文件”或“内存资源不足”
    TypeScript@HelloWorld!
    超详细Node安装教程
    进制转换
    菜鸟成长记
    ASP.NET Core中使用MialKit实现邮件发送
    VS未能正确加载 ”Microsoft.VisualStudio.Editor.Implementation.EditorPackate“包错误解决方法
    C#Winfrom Listview数据导入Excel
    安装研发服务器
  • 原文地址:https://www.cnblogs.com/zwube/p/6917089.html
Copyright © 2011-2022 走看看