Online PHP editor | refs for u9cZO

<?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; $time_start3 = microtime(true); echo substr_replace($var, '-', 1, 0) . "\n"; $time_end3 = microtime(true); echo "\nExecution Time: " . $time_end3 - $time_start3;