<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<!DOCTYPE html>
<html>
<body>
<h2 id="demo"></h2>
<button onclick="disp()">show</button>
<script>
function disp(){
var lk=Date()
var ku=lk.split(" ")
document.getElementById('demo').innerHTML =ku[4]
}
setInterval(disp,500)
</script>
</body>
</html>
