3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr=array(array("img","dummies","slides","01.jpg"),array("img","dummies","slides","01.jpg"),array("img","dummies","slides","01.jpg")); print_r($arr); echo $num_arr=count($arr); for($i=0;$i<$num_arr;$i++) { $new_key="key_".$i; $arr[$new_key] = $arr[$i]; unset($arr[$i]); } print_r($arr);
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, 5.5.0 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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 - 8.1.27, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Array ( [0] => Array ( [0] => img [1] => dummies [2] => slides [3] => 01.jpg ) [1] => Array ( [0] => img [1] => dummies [2] => slides [3] => 01.jpg ) [2] => Array ( [0] => img [1] => dummies [2] => slides [3] => 01.jpg ) ) 3Array ( [key_0] => Array ( [0] => img [1] => dummies [2] => slides [3] => 01.jpg ) [key_1] => Array ( [0] => img [1] => dummies [2] => slides [3] => 01.jpg ) [key_2] => Array ( [0] => img [1] => dummies [2] => slides [3] => 01.jpg ) )

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287.12 ms | 407 KiB | 359 Q