Ввод с клавиатуры multimap

//books.h
#pragma once
#include <string.h>
#include <iostream>
using namespace std;
 
class Books {
public:
    Books()
        : LastName(" "), FirstName(" "), phone(0)
    {}
 
    Books(string ln, string fn, int ph)
        : LastName(ln), FirstName(fn), phone(ph)
    {}
 
private:
    string LastName;
    string FirstName;
    int phone;
 
    friend ostream &operator<<(ostream &o, const Books &p);
};

//SonsoleApp.cpp
#include <map>
#include <string>
#include "Books.h"
using namespace std;
 
//--------------------------------------------------------------------------------------
 
//--------------------------------------------------------------------------------------
ostream &operator<<(ostream &o, const Books &p)
{
    o << "FirstName: " << p.FirstName << endl;
    o << "LastName: " << p.LastName << endl;
    o << "Phone: " << p.phone << endl;
    return o;
}
 
int main()
{
    multimap<char, Books> Nboock;
 
    Nboock.insert(make_pair('A', Books("Artem1", "Kalugniy1", 345678)));
    Nboock.insert(make_pair('B', Books("Artem2", "Kalugniy2", 345678)));
    Nboock.insert(make_pair('C', Books("Artem3", "Kalugniy3", 345679)));
;
    for (multimap<char, Books>::iterator It = Nboock.begin(); It != Nboock.end(); ++It)
        cout << It->second << endl;
    return 0;
    
}

auto sp = std::make_shared<Books>(FirstName, LastName, phone);
Nboock.insert({key, sp});
SortDate.insert({sp->phone, sp});