3v4l.org

run code in 300+ PHP versions simultaneously
<?php $msb = -1 * pow(2,63); for ($i=62; $i >= 0; $i--) { $result = pow(2,$i); $msb += $result; echo $msb,'\n'; } echo '<p>***',$msb,'****</p>';

preferences:
35.22 ms | 402 KiB | 5 Q