Someone

<?php
$num1 = $_POST[num1];
$num2 = $_POST[num2];
$numType1 = gettype ($num1);
$numType2 = gettype ($num2);
if ($num1 == "" || $num2 == ""){
$message = "Please input both numbers.";
} else if ($numType1 != (integer || double) || $numType2 != (integer || double)){
$message = "Not numbers!";
} else {
$message = "The multiplication of your numbers is: ". ($num1 * $num2) . ".";
}
?>
<html>
<body>
<form method="POST" action="<?php $_SERVER[PHP_SELF]; ?>">
<?php
echo $message;
echo "<br>";
?>
<table border="2">
<tr><td>First Number: </td><td><input type="text" name="num1"></td></tr>
<tr><td>Second Number: </td><td><input type="text" name="num2"></td></tr>
<tr><td><input type="submit" name="submit" value="Multiply!"></td></tr>
</table>
</body>
</html>