12.11 Class code and header files

https://www.learncpp.com/cpp-tutorial/class-code-and-header-files/

클래스 또한 header file에서 declaration하고
cpp 파일에서 definition을 완료해서 사용하곤 한다

Date.h:

#ifndef DATE_H
#define DATE_H

class Date
{
private:
    int m_year;
    int m_month;
    int m_day;

public:
    Date(int year, int month, int day);

    void SetDate(int year, int month, int day);

    int getYear() { return m_year; }
    int getMonth() { return m_month; }
    int getDay()  { return m_day; }
};

#endif

Date.cpp:

#include "Date.h"

// Date constructor
Date::Date(int year, int month, int day)
{
    SetDate(year, month, day);
}

// Date member function
void Date::SetDate(int year, int month, int day)
{
    m_month = month;
    m_day = day;
    m_year = year;
}