Question

i need to make a simple hash function for an id in my size_t function it works it need to print out numeric numbers and it has to be six numbers i think i need a loop here what it print out

input.txt

bob 4517898 102 tell rd

gill 4787456 103 hmm rd

output.txt

126990 bob 4517898 102 tell rd

126990 gill 4787456 103 hmm rd

#ifndef __CUSTOMER_H__
#define __CUSTOMER_H__

#include
#include

struct customer
{
   std::string name;
   std::string phone;
   std::string address;

   std::size_t hash() const;
};

inline std::istream& operator>>(std::istream& is, customer& m)
{
   is >> m.name >> m.phone >> e.address;
   std::getline(is, e.Address);
   return is;
}

inline std::ostream& operator<<(std::ostream& os, const customer& m)
{
   os << m.name<< "\t" << m.phone << "\t" << m.address;
}

#include

#include "customer.h"

std::size_t customer::hash() const
{

    std::hash<std::size_t>m;

    std::size_t id=1245;

    id =(id*101)+m(id);

    return id;

  
}

Answer 1

I have done what I am understand...

If you need any other, give me comment...

customer.h

#ifndef __CUSTOMER_H__

#define __CUSTOMER_H__

#include <fstream>

// #include

struct customer

{

std::string name;

std::string phone;

std::string address;

std::size_t hash() const;

};

inline std::istream& operator>>(std::istream& is, customer& m)

{

is >> m.name >> m.phone;

std::getline(is, m.address);

return is;

}

inline std::ostream& operator<<(std::ostream& os, const customer& m)

{

os <<m.hash()<<"\t"<< m.name<< "\t" << m.phone << "\t" << m.address;

}

#endif

customer.cpp

#include <iostream>

#include<cstdlib>

#include<ctime>

#include "customer.h"

std::size_t customer::hash() const

{

//std::hash<std::size_t> m;

srand(time(NULL));

std::size_t id=rand()%10000;

id =(id*101)+id;

return id;

}

int main(){

customer c;

std::cout<<"enter name phone address"<<std::endl;

std::cin>>c;

std::cout<<c<<std::endl;

}

Crkv-sdc@localhost 14032018]$ g++ custoner.cpp [rkv-sdc@localhost 14032018]$./a. out enter nane phone address bob 4517898 102 tell rd 533460 bob 4517898 102 tell rd