3v4l.org

run code in 300+ PHP versions simultaneously
<?php $peak = 5; for ($i = $peak; $i; --$i) { for ($n = $i; $n <= $peak; ++$n) { echo $n; } echo "\n"; }
Output for 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 - 8.3.25, 8.4.1 - 8.4.12
5 45 345 2345 12345

preferences:
152.2 ms | 407 KiB | 5 Q