I wish to get a number from a range of 1 - 80 and if not in that range alert box appear
<p>I am new to JavaScript and I need some help with this. I have a form and some JavaScript but having trouble adding an alert box for when the wrong range is entered. I wish for an alert box to be displayed range out of 1-80 is entered like, for example, 81.</p>

<pre><code>    &lt;script type="text/javascript"&gt;
// hide from old browsers

if (top != self) {
     top.location = self.location.href
}

// end script hiding
&lt;/script&gt;
&lt;script type="text/javascript"&gt;
// hide from non scripting browsers

function chooseRandom(form) {

var m = parseInt(form.lower.value);

var n = parseInt(form.upper.value) - m;

var output = Math.round(Math.random() * n) + m;

form.result.value = output;

}
// Clears the form

function clearForm(form) {

    form.upper.value="";

    form.lower.value="";

    form.upper.focus();

    form.upper.select();

}
&lt;/script&gt;
&lt;script type="text/javascript"&gt;
// calculates range from 1 - 80
var browName = navigator.appName;
var SiteID = 1;
var ZoneID = 80;
var browDateTime = (new Date()).getTime();
&lt;/script&gt;
</code></pre>
