pr11018.cpp

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////////////////////////////////////////
// File Name: pr11018.cpp
////////////////////////////////////////
#include <iostream>
#include <cstring>

////////////////////////////////////////
// Date class.
////////////////////////////////////////
class Date
{
    int mo, da, yr;
    char *month;

public:
    Date(int m = 0, int d = 0, int y = 0);
    ~Date();

    // Overloaded assignment operator.
    void operator=(const Date&);

    void display() const;
};

// The constructor definition.
Date::Date(int m, int d, int y)
{
    static char *mos[] =
    {
        "January", "February", "March", "April", "May",
        "June", "July", "August", "September", "October",
        "November", "December"
    };

    mo = m; da = d; yr = y;
    if (m != 0)
    {
        month = new char[std::strlen(mos[m-1])+1];
        std::strcpy(month, mos[m-1]);
    }
    else
        month = 0;
}

// The destructor definition.
Date::~Date()
{
    delete [] month;
}

// Display member function.
void Date::display() const
{
    if (month != 0)
        std::cout << month << ' ' << da
                  << ", " << yr << std::endl;
}

// Overloaded Date assignment.
void Date::operator=(const Date& dt)
{
    if (this != &dt)
    {
        mo = dt.mo;
        da = dt.da;
        yr = dt.yr;
        delete [] month;
        if (dt.month != 0)
        {
            month = new char [std::strlen(dt.month)+1];
            std::strcpy(month, dt.month);
        }
        else
            month = 0;
    }
}

////////////////////////////////////////
// The main() function.
////////////////////////////////////////
int main()
{
    // First date.
    Date birthday(6,24,1940);
    birthday.display();

    // Second date.
    Date newday(7,29,1941);
    newday.display();

    // Assign the first date to the second.
    newday = birthday;
    newday.display();

    return 0;
}