Untitled

<html>
    <body>
        <script>
            function go() {
                var a = document.getElementById("a").value;
                var b = document.getElementById("b").value;
                var result = "Twoje bmi to: " + a*b + " dddd. ";
                if (a*b<100) {
                    result += "Jestes tlusta swinia. ogarnij dupe";
                } else if (a*b>=100 && a*b<200) {
                    result += "Lubie w dupe.";
                } else {
                    result += "JP2GMD";
                }
                document.getElementById("result").innerHTML = result;
            }
        </script>
        <input type="text" id="a">
        <input type="text" id="b">
        <button onclick="go()">Click me</button>
        <div id="result" style="border: 1px solid black; padding:10px;">Tu bedzie wynik dzialania</div>
    </body>
</html>