$count = count($_GET);  
$i = 0;  
foreach ($_GET as $key => $value)
{  
    if ($i == $count - 1)
    {  
        $str .= $key . "=" . $value;  
    }
    else
    {  
        $str .= $key . "=" . $value . "&";  
    }  
    $i ++;  
}  
  
echo $str;