Online PHP editor | output for lchIO

<?php $tstart = microtime(true); $numberOfRandoms = 500; $uniques = array(); for($i = 0; $i < $numberOfRandoms; $i++) { do { $code = mt_rand(10000,99999); } while(in_array($code, $uniques); $uniques[] = $code; } $elapsed = microtime(true) - $tstart; echo $elapsed . PHP_EOL; $tstart = microtime(true); $numberOfRandoms = 500; $uniques = array(); do { $uniques[mt_rand(10000, 99999)] = true; } while(count(array_keys($uniques)) < $numberOfRandoms); $uniques = array_keys($uniques); $elapsed = microtime(true) - $tstart; echo $elapsed . PHP_EOL; $tstart = microtime(true); $uniques = range(10000, 99999); shuffle($uniques); $uniques = array_slice($uniques, 0, 500); $elapsed = microtime(true) - $tstart; echo $elapsed . PHP_EOL;