3v4l.org

run code in 300+ PHP versions simultaneously
<?php $STOP = 5; $i = $j = 0; while($STOP-- > 0) { if($i++ && $j++) { echo "2up\n"; } echo "i = $i ; j = $j\n"; }
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 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
i = 1 ; j = 0 i = 2 ; j = 1 2up i = 3 ; j = 2 2up i = 4 ; j = 3 2up i = 5 ; j = 4

preferences:
275.32 ms | 405 KiB | 456 Q