while($szam<=100)
                        {
$color = “white”;
if ( $szam%2 == 1 ) $color = “black";
                                echo("<td style='width: 30px; height: 30px; background-color: " . $color . "'>".$szam."</td>");
                                if($szam % 10 == 0) echo("</tr><tr>");

                                $szam++;
                        }