Calculate days

[amackeyb]

I need to do a program that calculate the days from a date whatever
since 20XX to January 1st. 2000. How can I do that??
I have this, is it correct???

# include <iostream.h>
# include <conio.h>
void main()
{
int month, day, year, c_year, c_month, t_days;

cout<<"Give a date dd/mm/yy: "<<endl;
cout<<"Day: ";
cin>>day;
cout<<"Month: ";
cin>>month;
cout<<"Year: ";
cin>>year;
clrscr();

c_year=year*365;
c_month=(month-1)*30;
t_days=c_year+c_month+day;

cout<<"Days from"<<day<<"/"<<month<<"/"<<year<<" to January 1st. 2000:
"<<t_days;
}

 

[red floyd]

I need to do a program that calculate the days from a date whatever
since 20XX to January 1st. 2000. How can I do that??
I have this, is it correct???

No, it is not. See blow.

# include <iostream.h>

# include <conio.h>

Non-standard header, don't know what it does.

using namespace std;

void main()

Undefined Behavior. Main *MUST* return int.
int main()

{
int month, day, year, c_year, c_month, t_days;

cout<<"Give a date dd/mm/yy: "<<endl;
cout<<"Day: ";
cin>>day;
cout<<"Month: ";
cin>>month;
cout<<"Year: ";
cin>>year;
clrscr();

you don't need to clear the screen. Kill this line (which
then also lets you remove that conio.h).

c_year=year*365;
c_month=(month-1)*30;

What about Jan, Feb, Mar, May, Jul, Aug, Oct, and Dec,
which don't have 30 days?

t_days=c_year+c_month+day;

cout<<"Days from"<<day<<"/"<<month<<"/"<<year<<" to January 1st. 2000:
"<<t_days;

cout << endl;

 

[Phlip]

Undefined Behavior. Main *MUST* return int.

I suspect it's ill-formed syntax. That occurs before any behavior.

 

[Jim Langston]

I need to do a program that calculate the days from a date whatever
since 20XX to January 1st. 2000. How can I do that??
I have this, is it correct???

# include <iostream.h>

# include <conio.h>

I wouldn't bother with this, unless you really wanted to.

void main()
{
int month, day, year, c_year, c_month, t_days;

cout<<"Give a date dd/mm/yy: "<<endl;
cout<<"Day: ";
cin>>day;
cout<<"Month: ";
cin>>month;
cout<<"Year: ";
cin>>year;
clrscr();

c_year=year*365;
c_month=(month-1)*30;

"Thirty days has September, April, June and November, all the rest have
thirty one, except for February which has 28, except on leap years has 31."

 

[Sumit Rajan]

"Thirty days has September, April, June and November, all the rest have
thirty one, except for February which has 28, except on leap years has 31."

Uh?!

 

[red floyd]

I suspect it's ill-formed syntax. That occurs before any behavior.

Whoops! You're right!

 

[Jim Langston]

Uh?!

er, 29. Yeah. That's what I meant to say

 

[Martin Steen]

I need to do a program that calculate the days from a date whatever
since 20XX to January 1st. 2000. How can I do that??
I have this, is it correct???

No, it's not that simple.

Visit http://www.javascript.martin-steen.de/astrodate.html
and view the page source. Then you see the "AstroDate"
formula in JavaScript (should be easy to understand for
C-programmers

Best regards, Martin

P.S. litte translation help for german/english:
Jahr = year
Monat = month
Tag = day

 

[red floyd]

er, 29. Yeah. That's what I meant to say

Easier one: "... all the rest have thirty one except for February which
is too complicated to discuss right now."