Output perpetual calendar

Displays the calendar of the current year and month based on the current computer time.

You can press the left and right arrow keys to turn to last month or next month.

You can press the up and down arrow keys to turn to the previous year or the next year.

# include & ltstdio.h & gt

# include & ltconio.h & gt

# include & ltstdlib.h & gt

# include & lttime.h & gt

Leap year (inter-year)

{

if（（year % 4 = = 0）& amp； & (year% 100! = 0)

||| (year% 400 == 0))

{

Returns1;

}

Returns 0;

}

Invalid display (cross-year, cross-month)

{

const char month _ str【】【4】= {““、“Jan“、“Feb“、“Mar“、“Apl“、

May, June, July, August, September, October, November and December};

const int month _ day【】= { 0，3 1，28，3 1，30，3 1，30，3 1，30，3 1，30，3 1 }；

int i，j，wdays，mdays，days

For(I = 1, days = 0; My< year; i++)

{

If (leap (I))

{

Days+= 366;

}

other

{

Days+= 365;

}

}

for（I = 1； I< month; i++)

{

if（I = = 2 & amp； & leap year)

{

Days+= 29;

}

other

{

days+= month _ day【I】；

}

}

Printf ("%s (%d) \ n", month_str [month], year);

Printf ("Monday Tuesday Wednesday Thursday Fri Saturday \ n");

wdays = days % 7；

for（j = 0； j & ltwdaysj++)

{

printf（“”）；

}

if（month = = 2 & amp； & leap year)

{

mdays = 29

}

other

{

mdays = month _ day【month】；

}

for（I = 1； I<= mdaysi++)

{

if（I & gt； 1 & amp； & Days% 7 == 0)

{

printf（“\ n“）；

}

printf（“% 4d“，I）；

Days = Days+1;

}

printf（“\ n-\ n“）；

}

Master ()

{

time _ t rawtime

struct tm * info

Int year, month;

char ch

Amp raw time;

info = local time（amp； raw time）；

year = info-& gt； TM _ year+ 1900；

month = info-& gt； TM _ mon+ 1；

while（ 1）

{

Display (year, month);

Printf ("left ... last month \ n");

Printf ("Right ... Next month \ n");

Printf ("Up ... Last year \ n");

Printf ("Down ... Next year \ n");

printf（“Esc.....exit \ n“）；

ch = getch（）；

Switch (channel)

{

Case 27://Ecs

Exit (0);

Case 32://Navigator

ch = getch（）；

if（ch = = 77）

{//Right

Year+= (month == 12)? 1:0;

Month = month%12+1;

}

else if（ch = = 75）

{//Left side

Year-= (month == 1)? 1:0;

month =（month-2+ 12）% 12+ 1；

}

else if（ch = = 72）

{//Up

Year-;

}

else if（ch = = 80）

{//Down

Year++;

}

System ("CLS");

}

}

}