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<?php $target_days = mktime(0,0,0,12,31,2013);// modify the birth day 12/31/2013 $today = time(); print "$today"; $diff_days = ($target_days - $today); $days = (int)($diff_days/86400); print "Days till next birthday: $days days!"; ?> - See more at: http://www.w3resource.com/php-exercises/php-date-exercises.php#sthash.xJA52BEw.dpuf
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.24, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0
1412426743Days till next birthday: -277 days! - See more at: http://www.w3resource.com/php-exercises/php-date-exercises.php#sthash.xJA52BEw.dpuf

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