3v4l.org

run code in 300+ PHP versions simultaneously
<?php $g = range(5,8); $h = array("a", "b", "c", "e"); for($i = 0; $i < count($g); $i++) { foreach ($h as $j) { echo $i.$j; break; } }
based on IKjec
Output for 7.2.0 - 7.2.32, 7.3.0 - 7.3.20, 7.4.0 - 7.4.8, 8.0.0alpha1 - alpha3
0a1a2a3a