POJ-2503 Babelfish---map or hash

Topic link:

Topic meaning:

Just like looking up a dictionary, based on the entered entry and the word to be queried, the query results are given (each word is not more than 10 in length)

Problem solving ideas:

The map container can be passed directly, but in order to practice hashing, you can also write a hash

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<string>
 5 #include<map>
 6 #include<set>
 7 #include<cmath>
 8 #include<algorithm>
 9 #include<vector>
10 #include<sstream>
11 #define lowbot(i) (i&(-i))
12 //#define Rotate(a, b) node(a.x + a.y - b.y, a.y + b.x - a.x)
13 using namespace std;
14 typedef long long ll;
15 const  int maxn = 1000 + 10 ;
 16  
17  const  int mod = 99973 ; // usually a prime number close to the total 
18  struct Hashtable
 19  {
 20      string s, t; // hash value 
21      Hashtable * next;
 22      Hashtable()
 23      {
 24          next = 0 ;
 25      }
 26  };
 27 Hashtable * Hash[mod];
 28  void Hash_Insert(string s, string t)//s对应t
29 {
30     int key = 0;
31     for(int i = 0; i < s.size(); i++)
32         key = (key * 26 + (s[i] - 'a')) % mod;
33     if(!Hash[key])//该key第一个元素
34     {
35         Hashtable * p = new Hashtable;
36         p->s = s;
37         p->t = t;
38         Hash[key] = p;
39     }
40     else
41     {
42         Hashtable *p = Hash[key];
43         while(p->next)p=p->next;
44         Hashtable* temp = new Hashtable;
45         temp->s = s;
46         temp->t = t;
47         p->next = temp;
48     }
49 }
50 void Find(string s)
51 {
52     int key = 0;
53     for(int i = 0; i < s.size(); i++)
54         key = (key * 26 + (s[i] - 'a')) % mod;
55     if(Hash[key])
56     {
57         Hashtable * temp = Hash[key];
58         while(temp)
59         {
60             if(temp->s == s)
61             {
62                 cout<<temp->t<<endl;
63                 return;
64             }
65             temp = temp->next;
66         }
67     }
68     cout<<"eh"<<endl;
69     return;
70 }
71 
72 int main()
73 {
74     string s, s1, s2;
75     while(getline(cin, s))
76     {
77         if(s.size() == 0)break;
78         stringstream ss(s);
79         ss >> s1 >> s2;
80         Hash_Insert(s2, s1);
81     }
82     while(cin >> s2)
83     {
84         Find(s2);
85     }
86     return 0;
87 }

POJ-2503 Babelfish---map or hash

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