ques15.cpp

#include <iostream>
#include <set>
#include <string>
using namespace std;
class person
{
private:
    string lastName;
    string firstName;
    long phoneNumber;
public:
    person() : lastName("blank"), firstName("blank"), phoneNumber(0L)
    { }
    person(string lname, string fname, long pho) : lastName(lname), firstName(fname), phoneNumber(pho)
    { }
    friend bool operator<(const person&, const person&);
    void display()
    {
        cout << endl << lastName << "\t" << firstName
        << "\tPhone: " << phoneNumber;
    }
    long get_phone() const { return phoneNumber; }
};

bool operator < (const person& p1, const person& p2)
{
    if(p1.lastName == p2.lastName)
        return (p1.firstName < p2.firstName) ? true : false;
    return (p1.lastName < p2.lastName) ? true : false;
}

class comparePersons
{
public:
    bool operator() (const person* ptrP1,
    const person* ptrP2) const { return *ptrP1 < *ptrP2; }
};
int main()
{
    multiset<person*, comparePersons> setPtrsPers;
    multiset<person*, comparePersons>::iterator iter;

    person* ptrP1 = new person("DEF", "ghi", 4157300);
    person* ptrP2 = new person("ABC", "def", 3327563);
    person* ptrP3 = new person("GHI", "jkl", 8435150);
    person* ptrP4 = new person("JKL", "mno", 9207404);
    person* ptrP5 = new person("MNO", "pqr", 6946473);
    person* ptrP6 = new person("ABC", "abc", 8435150);
    setPtrsPers.insert(ptrP1);
    setPtrsPers.insert(ptrP2);
    setPtrsPers.insert(ptrP3);
    setPtrsPers.insert(ptrP4);
    setPtrsPers.insert(ptrP5);
    setPtrsPers.insert(ptrP6);
    cout << "Set sorted when created:";
    for(iter=setPtrsPers.begin(); iter != setPtrsPers.end(); iter++ )
        (**iter).display();
    iter = setPtrsPers.begin();
    while( iter != setPtrsPers.end() )
    {
        delete *iter;
        setPtrsPers.erase(iter++);
    }
    cout << endl;

    return 0;
}