Untitled

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
    <h2 id="first">Enter 1st Number<input type="text"  /></h2>
     <h2 id ="second">Enter 2nd Number<input type="text"  /></h2>
     <h2 id="third">Enter 3rd Number<input type="text"  /></h2>
    <button onclick="test()">Sublit</button>


</div>

    <p id="sum"></p>
</form>
<script src="JavaScript.js"></script>

function test()
{
    var num1 = parseInt(document.getElementById("first").value)
    var num2 = parseInt(document.getElementById("second").value)
    var num3 = parseInt(document.getElementById("third").value)

    var z = num1 + num2 + num3
    document.getElementById("sum").innerHTML = z
}