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run code in 300+ PHP versions simultaneously
<?php $a = array('a', 'b', 'c'); /*foreach($a as $k=>$v){ if($k==1) unset($a[$k]); echo $k.' => '.$v.' ('.$a[$k].')'.PHP_EOL; }*/ for($k=count($a); $k>=0; $k--){ if($k==1) unset($a[$k]); echo $k.' ('.$a[$k].')'.PHP_EOL; } print_r($a);
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
Warning: Undefined array key 3 in /in/QbvuS on line 15 3 () 2 (c) Warning: Undefined array key 1 in /in/QbvuS on line 15 1 () 0 (a) Array ( [0] => a [2] => c )
Output for 5.3.0 - 5.3.29, 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 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 7.4.33
Notice: Undefined offset: 3 in /in/QbvuS on line 15 3 () 2 (c) Notice: Undefined offset: 1 in /in/QbvuS on line 15 1 () 0 (a) Array ( [0] => a [2] => c )
Output for 7.3.32 - 7.3.33, 7.4.26
3 () 2 (c) 1 () 0 (a) Array ( [0] => a [2] => c )
Output for 4.3.10 - 4.3.11, 4.4.0 - 4.4.9, 5.0.2 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Notice: Undefined offset: 3 in /in/QbvuS on line 15 3 () 2 (c) Notice: Undefined offset: 1 in /in/QbvuS on line 15 1 () 0 (a) Array ( [0] => a [2] => c )
Output for 4.3.0 - 4.3.9, 5.0.0 - 5.0.1
Notice: Undefined offset: 3 in /in/QbvuS on line 15 Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/QbvuS on line 15 3 ()PHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/QbvuS on line 15 2 (c)PHP_EOL Notice: Undefined offset: 1 in /in/QbvuS on line 15 Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/QbvuS on line 15 1 ()PHP_EOL Notice: Use of undefined constant PHP_EOL - assumed 'PHP_EOL' in /in/QbvuS on line 15 0 (a)PHP_EOLArray ( [0] => a [2] => c )
preferences:
270.38 ms | 403 KiB | 460 Q