3v4l.org

run code in 300+ PHP versions simultaneously
<?php $dt = new DateTime; for ($w = 52; $w <= 54; $w++) { $dt->setISODate(2013, $w); echo $dt->format('Y-m-d W') . "\n\n"; }
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
2013-12-23 52 2013-12-30 01 2014-01-06 02

preferences:
46.79 ms | 408 KiB | 5 Q