explanation needed!

[mahmoud.mnea]

hello, I found one of my brothers old college assignments and I would like a quick explanation of the code. I know what it does, I compiled the code and the program asks you to enter a year between 2000 and 2099 and prints out the calendar for that year.
if somebody could explain it to me because iam a huge noob when it come to programming..thanx in advance.

#include<stdio.h>
#include<windows.h>
COORD coord={0,0}; void gotoxy(int x,int y)
{ coord.X=x; coord.Y=y; SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),coord); }
main()
{
int year,Day_of_month[12]={31,28,31,30,31,30,31,31,30,31,30,31};
char
Month[12][50]={" January"," February"," March"," April"," May"," June"," July"," August","September"," October"," November"," December"};
int month,day,first_day_of_the_year; printf("\nEnter the year "); scanf("%d",&year);
system("cls"); while(year<2000||year>2099)
{
printf("wrong input\nplease enter again "); scanf("%d",&year);
system("cls");
}
if(year%4==0)
Day_of_month[1]=29; first_day_of_the_year=(((year+3-2000)/4)+(year-2000))%7; for(month=0;month<12;month++)
{
gotoxy((3*(month%3)+1)*8+(month%3)*3,12*(month/3)); printf("%s",Month[month]);
gotoxy( (27*(month%3)+3),12*(month/3)+1);
printf("Sa Su Mo Tu We Th Fr");
for(day=1;day<=Day_of_month[month];day++)
{
gotoxy(27*(month%3)+3+((first_day_of_the_year+day- 1)%7)*3,2+12*(month/3)+(first_day_of_the_year+day-1)/7);
printf("%2d",day);
} first_day_of_the_year=(first_day_of_the_year+Day_of_month[month])%7; }
}

[userxbw]

personally you being a noob, and you do not possess the comprehend of what the code is doing just by looking at it yourself.

I'd say it'd be better for you to take a few steps backwards and look for some more of your brothers code that was say his first week in programming class. but that is my option.

[GReaper]

You could start by formatting this mess a little better, maybe then you'd be able to understand it a little more:

#include<stdio.h>
#include<windows.h>

COORD coord= {0,0};
void gotoxy(int x,int y)
{
    coord.X=x;
    coord.Y=y;
    SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),coord);
}

main()
{
    int year,Day_of_month[12]= {31,28,31,30,31,30,31,31,30,31,30,31};
    char Month[12][50]= {
    	" January"," February"," March"," April"," May"," June",
    	" July"," August","September"," October"," November"," December"
    };
    int month,day,first_day_of_the_year;
    
    printf("\nEnter the year ");
    scanf("%d",&year);
    system("cls");
    while(year<2000||year>2099) {
        printf("wrong input\nplease enter again ");
        scanf("%d",&year);
        system("cls");
    }
   
    if(year%4==0) {
        Day_of_month[1]=29;
    }
    first_day_of_the_year=(((year+3-2000)/4)+(year-2000))%7;

    for(month=0; month<12; month++) {
        gotoxy((3*(month%3)+1)*8+(month%3)*3,12*(month/3));
        printf("%s",Month[month]);
        gotoxy( (27*(month%3)+3),12*(month/3)+1);
        printf("Sa Su Mo Tu We Th Fr");

        for(day=1; day<=Day_of_month[month]; day++) {
            gotoxy(27*(month%3)+3+((first_day_of_the_year+day- 1)%7)*3,
            	   2+12*(month/3)+(first_day_of_the_year+day-1)/7);
            printf("%2d",day);
        }
        first_day_of_the_year=(first_day_of_the_year+Day_of_month[month])%7;
    }
}

[john.c]

Your question is too general. What part don't you understand?

#include <stdio.h>
#include <stdlib.h>

#ifdef _WIN32

#include <windows>

#define CLEAR_COMMAND "cls"

void gotoxy(int x, int y)
{
  COORD coord = (COORD){x, y};
  SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), coord);
}

#else

#define CLEAR_COMMAND "clear"

void gotoxy(int x, int y)
{
    printf("\033[%d;%dH", y + 1, x + 1);
}

#endif


int main()
{
  int year, Day_of_month[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  char Month[12][15] = {
    "January", "February", "March",     "April",   "May",      "June",
    "July",    "August",   "September", "October", "November", "December"};
  int month, day, first_day_of_the_year;

  while (1)
  {
    printf("Enter the year ");
    scanf("%d", &year);
    if (year >= 2000 && year <= 2099)
        break;
    printf("Year must be from 2000 to 2099\n");
  }

  system(CLEAR_COMMAND);

  if (year % 4 == 0) // works because years are restricted to 2000 to 2099
    Day_of_month[1] = 29;

  first_day_of_the_year = (((year + 3 - 2000) / 4) + (year - 2000)) % 7;

  for (month = 0; month < 12; month++)
  {
    gotoxy((3 * (month % 3) + 1) * 8 + (month % 3) * 3, 8 * (month / 3));
    printf("%s", Month[month]);
    gotoxy((27 * (month % 3) + 3), 8 * (month / 3) + 1);
    printf("Sa Su Mo Tu We Th Fr");
    for (day = 1; day <= Day_of_month[month]; day++)
    {
      gotoxy(27 * (month % 3) + 3 + ((first_day_of_the_year + day - 1) % 7) * 3,
             2 + 8 * (month / 3) + (first_day_of_the_year + day - 1) / 7);
      printf("%2d", day);
    }
    first_day_of_the_year = (first_day_of_the_year + Day_of_month[month]) % 7;
  }
  
  printf("\n\n");

  return 0;
}

It's not a very good algorithm, anyway, since you don't really need the positioning code (gotoxy). It can be done line-by-line easily enough.

[mahmoud.mnea]

Your question is too general. What part don't you understand?

#include <stdio.h>
#include <stdlib.h>

#ifdef _WIN32

#include <windows>

#define CLEAR_COMMAND "cls"

void gotoxy(int x, int y)
{
  COORD coord = (COORD){x, y};
  SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), coord);
}

#else

#define CLEAR_COMMAND "clear"

void gotoxy(int x, int y)
{
    printf("\033[%d;%dH", y + 1, x + 1);
}

#endif


int main()
{
  int year, Day_of_month[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  char Month[12][15] = {
    "January", "February", "March",     "April",   "May",      "June",
    "July",    "August",   "September", "October", "November", "December"};
  int month, day, first_day_of_the_year;

  while (1)
  {
    printf("Enter the year ");
    scanf("%d", &year);
    if (year >= 2000 && year <= 2099)
        break;
    printf("Year must be from 2000 to 2099\n");
  }

  system(CLEAR_COMMAND);

  if (year % 4 == 0) // works because years are restricted to 2000 to 2099
    Day_of_month[1] = 29;

  first_day_of_the_year = (((year + 3 - 2000) / 4) + (year - 2000)) % 7;

  for (month = 0; month < 12; month++)
  {
    gotoxy((3 * (month % 3) + 1) * 8 + (month % 3) * 3, 8 * (month / 3));
    printf("%s", Month[month]);
    gotoxy((27 * (month % 3) + 3), 8 * (month / 3) + 1);
    printf("Sa Su Mo Tu We Th Fr");
    for (day = 1; day <= Day_of_month[month]; day++)
    {
      gotoxy(27 * (month % 3) + 3 + ((first_day_of_the_year + day - 1) % 7) * 3,
             2 + 8 * (month / 3) + (first_day_of_the_year + day - 1) / 7);
      printf("%2d", day);
    }
    first_day_of_the_year = (first_day_of_the_year + Day_of_month[month]) % 7;
  }
  
  printf("\n\n");

  return 0;
}

It's not a very good algorithm, anyway, since you don't really need the positioning code (gotoxy). It can be done line-by-line easily enough.

what I dont get is the system(cls) function, what does it do specifically ??

[Salem]

I suppose you could comment it out, then learn something through observing cause and effect.

[jimblumberg]

I found one of my brothers old college assignments and I would like a quick explanation of the code.

I recommend you ask your brother.

[userxbw]

system(cls)

programming acronyms

you might find it in here

List of computing and IT abbreviations - Wikipedia

[Matticus]

I recommend you ask your brother.

This makes me miss the "like" feature...