zoukankan      html  css  js  c++  java
  • ZOJ 3228 Searching the String

    Searching the String

    Time Limit: 7000ms
    Memory Limit: 129872KB
    This problem will be judged on ZJU. Original ID: 3228
    64-bit integer IO format: %lld      Java class name: Main

    Little jay really hates to deal with string. But moondy likes it very much, and she's so mischievous that she often gives jay some dull problems related to string. And one day, moondy gave jay another problem, poor jay finally broke out and cried, " Who can help me? I'll bg him! "

    So what is the problem this time?

    First, moondy gave jay a very long string A. Then she gave him a sequence of very short substrings, and asked him to find how many times each substring appeared in string A. What's more, she would denote whether or not founded appearances of this substring are allowed to overlap.

    At first, jay just read string A from begin to end to search all appearances of each given substring. But he soon felt exhausted and couldn't go on any more, so he gave up and broke out this time.

    I know you're a good guy and will help with jay even without bg, won't you?

    Input

    Input consists of multiple cases( <= 20 ) and terminates with end of file.

    For each case, the first line contains string A ( length <= 10^5 ). The second line contains an integer N ( N <= 10^5 ), which denotes the number of queries. The next N lines, each with an integer type and a string a ( length <= 6 ), type = 0 denotes substring a is allowed to overlap and type = 1 denotes not. Note that all input characters are lowercase.

    There is a blank line between two consecutive cases.

    Output

    For each case, output the case number first ( based on 1 , see Samples ).

    Then for each query, output an integer in a single line denoting the maximum times you can find the substring under certain rules.

    Output an empty line after each case.

    Sample Input

    ab
    2
    0 ab
    1 ab
    
    abababac
    2
    0 aba
    1 aba
    
    abcdefghijklmnopqrstuvwxyz
    3
    0 abc
    1 def
    1 jmn
    

    Sample Output

    Case 1
    1
    1
    
    Case 2
    3
    2
    
    Case 3
    1
    1
    0
    
    

    Hint

    In Case 2,you can find the first substring starting in position (indexed from 0) 0,2,4, since they're allowed to overlap. The second substring starts in position 0 and 4, since they're not allowed to overlap.

    For C++ users, kindly use scanf to avoid TLE for huge inputs.

     

    Source

    Author

    LI, Jie
     
    解题:Trie图或者AC自动机
     1 #include <bits/stdc++.h>
     2 using namespace std;
     3 const int maxn = 1000010;
     4 struct Trie{
     5     int ch[maxn][26],fail[maxn],pre[maxn],cnt[maxn][2];
     6     int len[maxn],tot;
     7     int newnode(){
     8         memset(ch[tot],0,sizeof ch[tot]);
     9         pre[tot] = cnt[tot][0] = cnt[tot][1] = 0;
    10         fail[tot] = len[tot] = 0;
    11         return tot++;
    12     }
    13     void init(){
    14         tot = 0;
    15         newnode();
    16     }
    17     int insert(char *str,int root = 0){
    18         for(int i = 0; str[i]; ++i){
    19             int &x = ch[root][str[i]-'a'];
    20             if(!x) x = newnode();
    21             root = x;
    22             len[root] = i + 1;
    23         }
    24         return root;
    25     }
    26     void build(int root = 0){
    27         queue<int>q;
    28         for(int i = 0; i < 26; ++i)
    29             if(ch[root][i]) q.push(ch[root][i]);
    30         while(!q.empty()){
    31             root = q.front();
    32             q.pop();
    33             for(int i = 0; i < 26; ++i){
    34                 int &x = ch[root][i];
    35                 if(x){
    36                     fail[x] = ch[fail[root]][i];
    37                     q.push(x);
    38                 }else x = ch[fail[root]][i];
    39             }
    40         }
    41     }
    42     void query(char *str,int root = 0){
    43         for(int i = 0; str[i]; ++i){
    44             int x = root = ch[root][str[i]-'a'];
    45             while(x){
    46                 ++cnt[x][0];
    47                 if(i - pre[x] + 1 >= len[x]){
    48                     pre[x] = i + 1;
    49                     ++cnt[x][1];
    50                 }
    51                 x = fail[x];
    52             }
    53         }
    54     }
    55 }ac;
    56 char str[100010],ss[100];
    57 int pos[100010],ty[100010],n,cs = 1;
    58 int main(){
    59     while(~scanf("%s",str)){
    60         ac.init();
    61         scanf("%d",&n);
    62         for(int i = 0; i < n; ++i){
    63             scanf("%d%s",ty + i,ss);
    64             pos[i] = ac.insert(ss);
    65         }
    66         ac.build();
    67         ac.query(str);
    68         printf("Case %d
    ",cs++);
    69         for(int i = 0; i < n; ++i)
    70             printf("%d
    ",ac.cnt[pos[i]][ty[i]]);
    71         putchar('
    ');
    72     }
    73     return 0;
    74 }
    View Code
  • 相关阅读:
    苏州大学2017年复试试题
    四川大学2019年复试试题
    四川大学2009年复试试题
    华东师范大学2019年复试试题
    华东师范大学2018年复试试题
    华东师范大学2017年复试试题
    华东师范大学2016年复试试题
    中国科学院大学2020年高等代数考研试题
    中国科学院大学2020年数学分析考研试题
    中国科学技术大学2020年高等代数考研试题
  • 原文地址:https://www.cnblogs.com/crackpotisback/p/4937337.html
Copyright © 2011-2022 走看看