3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = []; // make some array for testing for($i=0; $i < 100; $i++) $array["key$i"] = $i; for($i=0; $i < 1000000; $i++) { reset($array); $firstKey = key($array); }
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 - 8.1.31, 8.2.0 - 8.2.26, 8.3.0 - 8.3.15, 8.4.1 - 8.4.2
preferences:
86.16 ms | 408 KiB | 5 Q