#include <stdio.h>          //  Ver: 01



enum Day {Monday = 1, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday};


Day yesterday,
        today,
     tomorrow;


//////////////////////////////////////////////////////
int main()                                          //
{

    today = Tuesday;

    printf("yesterday = %d\n", yesterday);
    printf("today     = %d\n", today    );
    printf("tomorrow  = %d\n", tomorrow );
}







/*

#include <stdio.h>          //  Ver: 02



enum Day {Monday = 1, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday};


Day yesterday,
        today,
     tomorrow;

void Change_today(Day);
void Show_the_day(   );


//////////////////////////////////////////////////////
int main()                                          //
{

    today = Tuesday;

    Show_the_day();

    Change_today(Sunday);

    Show_the_day();
}

//////////////////////////////////////////////////////
void Change_today(Day d)                            //
{

     yesterday = static_cast<Day>(d - 1);
     today     = d;
     tomorrow  =            (Day)(d + 1);

     if(d == Sunday) tomorrow  =  Monday;
     if(d == Monday) yesterday =  Sunday;
}



//////////////////////////////////////////////////////
void Show_the_day()                                 //
{

     printf("yesterday = %d\n", yesterday);
     printf("today     = %d\n", today    );
     printf("tomorrow  = %d\n", tomorrow );
     printf(" - - - - - - - - - - - - \n");
}


*/



/*
#include <stdio.h>          //  Ver: 03



enum Day {Monday = 1, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday};





Day yesterday,
        today,
     tomorrow;

void Change_today(Day);
void Show_the_day(   );


//////////////////////////////////////////////////////
int main()                                          //
{

    today = Tuesday;

    Show_the_day();

    Change_today(Sunday);

    Show_the_day();
}

//////////////////////////////////////////////////////
void Change_today(Day d)                            //
{

     yesterday = static_cast<Day>(d - 1);
     today     = d;
     tomorrow  =            (Day)(d + 1);

     if(d == Sunday) tomorrow  =  Monday;
     if(d == Monday) yesterday =  Sunday;
}



//////////////////////////////////////////////////////
void Show_the_day()                                 //
{

    char szDays[8][11] = {      "void",
                              "Monday",
                             "Tuesday",
                           "Wednesday",
                            "Thursday",
                              "Friday",
                            "Saturday",
                              "Sunday"};


     printf("yesterday = %9s\n", szDays[yesterday]);
     printf("today     = %9s\n", szDays[today    ]);
     printf("tomorrow  = %9s\n", szDays[tomorrow ]);
     printf(" - - - - - - - - - - - - \n");
}

*/