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run code in 300+ PHP versions simultaneously
<?php $some_array = array (0 => 1, 'x'=> 1, 2 => 1, 'a'=> 1, 1 => 1, 'z'=> 1); ksort($some_array); echo(join("", array_keys($some_array)));

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62.84 ms | 402 KiB | 5 Q