Hash Table application (C ++ implementation)

Problem description: design a hash table to query telephone numbers and implement the following functions:
(1) assume that each record has the following data items: phone number, user name, and address.
(2) In the hosts file and displayed on the screen, the number of records should not be less than 30, and a hash table is created with the telephone number and user name as keywords respectively.
(3) use pseudo-random detection and re-hash to resolve conflicts.
(4) search for and display the records of the given phone number; search for and display the records of the given user name.
(5) Save the unfound result to out.txt. A prompt statement is required before the search result is displayed.

Code:

// Myhashtable. cpp: defines the entry point of the console application. /// Design a hash table to query telephone numbers. // Note: first, the data read from the old.txt file is created before the program is run. // second, the data is randomly generated by the system, when the program runs, it is generated by the random number generator and the generated records are saved to the new.txt file. // Problem: Garbled characters are displayed when randomly generated files are used. # include "stdafx. H "# include <fstream> // file stream # include <iostream> # include <string> using namespace STD; const int d [] = {3, 5, 8, 11, 13, 14, 19,21}; // pre-scheduled random number const int hash_maxsize = 50; // hash table length // record information type class datainfo {public: datainfo (); // default constructor friend ostream & operator <(ostream & out, const datainfo & datainfo); // overload output operator // friend class hashtable; // Private: string name; // name string phone; // phone number S Tring address; // address char sign; // The identifier of the conflict. '1' indicates a conflict, and '0' indicates no conflict.}; datainfo: datainfo (): name (""), phone (""), address (""), sign ('0') {} ostream & operator <(ostream & out, const datainfo & datainfo) // reload the output operator {cout <"name:" <datainfo. name <"Phone:" <datainfo. phone <"Address:" <datainfo. address <Endl; Return out;} // class hashtable {public: hashtable (); // default constructor ~ Hashtable (); // destructor int random (INT key, int I); // handle conflicting void hashname (datainfo * datainfo) by means of pseudo-random number detection and hash ); // create a hash table int rehash (INT key, string Str) with the name as the keyword ); // use the hash method to handle conflicts. Pay attention to the handling of conflicts and void hashphone (datainfo * datainfo) such as the link address method. // create a hash table void Hash (char * fname, int N); // create a hash table // fname is the name of the data storage file, used for input data, and N is the user-selected search method int findname (string name ); // search for the key code int findphone (string phone) corresponding to the record in the hash table by name; // search for the key code void outhas corresponding to the record in the hash table by phone H (INT key); // output the void OUTFILE (string name, int key) record corresponding to the keyword code in the hash table ); // output the unfound record void rafile () When not found; // generate a random file and save the file in the new.txt file void writemedildtxt (); // write data before running // Private: datainfo * value [hash_maxsize]; int length; // hash table length}; hashtable: hashtable (): length (0) // default constructor {// memset (value, null, hash_maxsize * sizeof (datainfo *); For (INT I = 0; I