3v4l.org

run code in 200+ php & hhvm versions
Bugs & Features
<?php for( $i = 1; $i < 20; $i++ ) { echo 1 * ( 1 * $i + pow( -1, $i ) - 1 ) . ', '; }
based on cCCCW
Output for 4.3.0 - 7.2.0
-1, 2, 1, 4, 3, 6, 5, 8, 7, 10, 9, 12, 11, 14, 13, 16, 15, 18, 17,