<html>
<head>
<title>factorial</title>
<script type="text/javascript" >
function factorial()
{
var a=document.getElementById("tx1").value;
var n=parseInt(a)
var fact=1;
for(var i=1;i<=n;i++)
fact=fact*i;
document.getElementById("tx2").value=fact;
}
</script>
</head>
<body>
<h3>finding factorial</h3>
<form action="" >
<p>enter a number <input type="text"id="tx1"size="20"/><br/>
factoril<input type="text"id="tx2"size="20"/><br/>
<input type="button"value="find"onclick="factorial()"/>
<input type="reset"value="clear"/>
</p>
</form>
</body>
</html>