Online PHP editor | refs for nj0KD

<?php $var = "12345"; $time_start = microtime(true); echo $var[0] . "-" . substr($var,1) . "\n"; $time_end = microtime(true); echo "\nExecution Time: " . $time_end - $time_start . "\n"; $time_start2 = microtime(true); echo str_replace($var[0], $var[0].'-', $var) . "\n"; $time_end2 = microtime(true); echo "\nExecution Time: " . $time_end2 - $time_start2;