Dashatize it

dashatize.php

<?php 

/**
 * Dashatize it
 *
 * @author  Phan Vu Hoang <[email protected]>
 */

require '../vendor/autoload.php';

function dashatize( $num ) {
	$str = (string)($num);
	$str = str_replace('-', '', $str);
	$len = strlen($str);
	$ret = [];
	
	for ($i=0; $i < $len; $i++) { 
		# code...
		echo $str[$i] . ' ';
		if ( (int)$str[$i] % 2 == 0) {
			$ret[] = $str[$i];
		} else {
			$ret[] = '-' .$str[$i] . '-';
		}
	}

	$ret = implode('', $ret);
	if($ret[0]=='-') $ret = substr($ret, 1);
	if(substr($ret, -1)=='-') $ret = substr($ret, 0, -1);
	$ret = str_replace('--', '-', $ret);
	
	return $ret;	
}