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run code in 300+ PHP versions simultaneously
<?php $str = "abcdefghijklmn"; $print = strrev($str); $st=""; for($i = 0;$i<$print.length;$i=$i+2) { if($i < $print.length - 1) $st .= substr($print,$i,$i+1); echo $st; }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Fatal error: Uncaught Error: Undefined constant "length" in /in/CpKXO:5 Stack trace: #0 {main} thrown in /in/CpKXO on line 5
Process exited with code 255.
Output for 7.4.0 - 7.4.33
Deprecated: The behavior of unparenthesized expressions containing both '.' and '+'/'-' will change in PHP 8: '+'/'-' will take a higher precedence in /in/CpKXO on line 7 Warning: Use of undefined constant length - assumed 'length' (this will throw an Error in a future version of PHP) in /in/CpKXO on line 5
Output for 7.2.0 - 7.2.33, 7.3.12 - 7.3.33
Warning: Use of undefined constant length - assumed 'length' (this will throw an Error in a future version of PHP) in /in/CpKXO on line 5
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20
Notice: Use of undefined constant length - assumed 'length' in /in/CpKXO on line 5

preferences:
212.51 ms | 404 KiB | 315 Q