3v4l.org

run code in 300+ PHP versions simultaneously
<?php $mid = 123; $csum = 0; foreach(str_split($mid) as $m){ $csum+= $m; } $csum = $csum % 10; echo $csum;
Output for 7.1.25 - 7.1.32, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
6

preferences:
160.98 ms | 407 KiB | 5 Q