3v4l.org

run code in 300+ PHP versions simultaneously
<?php $test = NULL; $vals = array('prvá', 'druha', 'tretia', 'stvrta'); foreach($vals as $k => $val) { $test .= $k . '-' . $val . '+'; } echo $test;
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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
0-prvá+1-druha+2-tretia+3-stvrta+

preferences:
275.5 ms | 406 KiB | 460 Q