3v4l.org

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<?php $start = "2015-09-01"; $end = date('Y-m-d', strtotime("$start +1 months")); $period = floor((strtotime($end) - strtotime($start))/(24*60*60)); for($i = 0; $i < $period; $i++){ if(in_array(date('l',strtotime("$start +$i day")),["Monday","Friday"])) echo date('l d M, Y',strtotime("$start +$i day"))."\n"; }
Output for 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Friday 04 Sep, 2015 Monday 07 Sep, 2015 Friday 11 Sep, 2015 Monday 14 Sep, 2015 Friday 18 Sep, 2015 Monday 21 Sep, 2015 Friday 25 Sep, 2015 Monday 28 Sep, 2015

preferences:
299.62 ms | 404 KiB | 385 Q