calculations

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Test</title>
</head>
<body>
    <label for="">α</label>
    <input id="a" type="number" placeholder="Εισάγετε το α"><br>
    <label for="">β</label>
    <input id="b" type="number" placeholder="Εισάγετε το β"><br>
    <p id="c"></p>
    <button onclick="add()">υπολογισμός</button>
    <script>
        function add(){
            var a = document.getElementById('a').value;
            console.log(a);
            var b = document.getElementById('b').value;
            console.log(b);
            var c = parseFloat(a) + parseFloat(b);
            document.getElementById('c').innerHTML = c;
        }
    </script>
</body>
</html>