Discordian date: Difference between revisions

=={{header|C}}==

<lang C>#include <string.h>

#include <malloc.h>

#include <stdlib.h>

#include <stdio.h>

#include <time.h>

#define season( x ) ((x) == 0 ? "Chaos" :\

(x) == 1 ? "Discord" :\

(x) == 2 ? "Confusion" :\

(x) == 3 ? "Bureaucracy" :\

"The Aftermath")

#define date( x ) ((x)%73 == 0 ? 73 : (x)%73)

#define leap_year( x ) ((x) % 400 == 0 || (((x) % 4) == 0 && (x) % 100))

char * ddate( int y, int d ){

int dyear = 1166 + y;

char * result = malloc( 100 * sizeof( char ) );

if( leap_year( y ) ){

if( d == 60 ){

sprintf( result, "St. Tib's Day, YOLD %d", dyear );

return result;

} else if( d >= 60 ){

-- d;

}

}

sprintf( result, "%s %d, YOLD %d", season( d/73 ), date( d ), dyear );

return result;

}

int day_of_year( int y, int m, int d ){

int month_lengths[ 12 ] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

for( ; m > 1; m -- ){

d += month_lengths[ m - 2 ];

if( m == 3 && leap_year( y ) ){

++ d;

}

}

return d;

}

int main( int argc, char * argv[] ){

time_t now;

struct tm * now_time;

int year, doy;

if( argc == 1 ){

now = time( NULL );

now_time = localtime( &now );

year = now_time->tm_year + 1900; doy = now_time->tm_yday + 1;

} else if( argc == 4 ){

year = atoi( argv[ 1 ] ); doy = day_of_year( atoi( argv[ 1 ] ), atoi( argv[ 2 ] ), atoi( argv[ 3 ] ) );

}

printf( "%s\n", ddate( year, doy ) );

return 0;

}</lang>

Demonstration:

<pre>$ ./ddate #today

Chaos 7, YOLD 3177

$ ./ddate 2011 1 7

Chaos 7, YOLD 3177

$ ./ddate 2012 2 28

Chaos 59, YOLD 3178

$ ./ddate 2012 2 29

St. Tib's Day, YOLD 3178

$ ./ddate 2012 3 1

Chaos 60, YOLD 3178

$ ./ddate 2010 7 22

Confusion 57, YOLD 3176

</pre>