//Why not run it and see the results? Not every three months? Why don't you change it yourself and just add a line break?
# include & ltstdio.h & gt
# include & ltwindows.h & gt
# include & ltstdlib.h & gt
int？ Runnian (int? Year); //Judge whether it is a leap year.
int？ longmonth？ (int？ Year, int? Mouth) //Judge the number of days in each month
int？ year _ fristday？ (int？ Year); //Judge what day is the first day of New Year's Day every year.
//int？ month _ first day(int？ Year, int? Month); //Determine the day of the week on the first day of each month.
int？ Master ()
{
int？ Year;
int？ j，month= 1，I，c=0，day，weekday，d=0，a；
System ("color? 3E”)；
Printf ("Please? Input? Year. \ n ")；
Sleep (1000);
Printf ("for example, 2015 \ n");
Scanf("%d ",& year);
printf("\n\n\n？ %d year \n\n ",year);
System ("CLS");
Weekday = year _ Friday (year);
D = working days;
//? Printf("%d ",working day); (Check whether the meta function is correct)
for(I = 1； I< 13; i++)
{
Printf("%d month \n ",i);
printf("-\ n ")；
printf(" SUNMONTUEWEDTHUFRISAT \ n ")；
printf("-\ n ")；
//printf("% d ",days);
if(month== 1)
for(j = 0； J< working days; j++)
printf(" ")；
other
{
D =(d+ days)% 7;
//? D = d+ working days;
if(d & lt； 7)
for(j = 0； j & ltd； j++)
printf(" ")；
other
{
d = d-7；
for(j = 0； j & ltd； j++)
printf(" ")；
}
}
a = d+ 1；
Day=longmonth (year, month);
for(c = 1； C< (day+1); c++，a++)
{
printf("？ %2d”，c)；
If (a%7==0)
printf(" \ n ")；
}
printf(" \ n \ n ")；
month++；
//Sleep (1000);
}
getchar()；
getchar()；
Return? 0;
}
int？ longmonth？ (int？ Year, int? Month)
{
int？ Month _ day, a;
A = Runnian (year);
If (a== 1)
{
if(month = = 1 | | month = = 3 | | month = = 5 | | month = = 7 | | month = = 8 | | month = = 10 | | month = = 12)
month _ day = 3 1；
If (month = = 2 ||| month = = 4 ||| month = = 6 ||| month = = 9 | | month = =1)
Month _ day = 30;
if(month==2)
Month _ day = 29;
}
other
{
if(month = = 1 | | month = = 3 | | month = = 5 | | month = = 7 | | month = = 8 | | month = = 10 | | month = = 12)
month _ day = 3 1；
If (month = = 2 ||| month = = 4 ||| month = = 6 ||| month = = 9 | | month = =1)
Month _ day = 30;
if(month==2)
Month _ day = 28;
}
Return? Month _ day;
}
int？ year _ fristday？ (int？ Year)
{
int？ n，b；
N = year-1900;
n = n/4+n+ 1；
b = n % 7；
Return? b；
}
int？ Runnian (int? Year)
{
int？ n；
If (year% 100==0)
{
If (year %400==0)
n = 1；
other
n = 0；
}
other
{
If (year %4==0)
n = 1；
other
n = 0；
}
Return? n；
}
//@ Author? zjb