gistfile1.php

		$cc_left = substr($cc_number, 0, 4);
		$cc_tmp_right = substr($cc_number, 4);
		$cc_center = substr($cc_tmp_right, 0, 8);
		$cc_right = substr($cc_tmp_right, 8);
		
		echo $cc_number."<br />";		
		echo $cc_left.$cc_center.$cc_right;