3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = [ 'a' => 1, 2 => 1, 'three' => 3, 4 => 5, 6 => 7, ]; foreach ($a as &$v) $v++; var_dump($a);

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46.48 ms | 402 KiB | 5 Q