<?php
 $number = '8(911)-506-56-56';
 $regexp = '/[0-9]{1}[(?0-9)?]{3}[-?0-9]{2}[-?0-9]{3}[-?0-9]{2}/';
 $matches = array();
 if(preg_match($regexp,$number,$matches)){
 	echo"Allright, thats the correct number\n ";
 }
 	else{
 		echo"Something wrong, lets try it again\n";
 	}
 
 var_dump($matches);

// your code goes here