Untitled

<script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>
<script type="text/javascript">
function _submit(){
  $("p").html("YOU ARE HERE 1");

  var username = $('input#x').val();
  var password = $('input#y').val();
  var mydata = $('.myform').serialize();

  if (username != "" && password != "") {
    $.ajax({
      data: mydata,
      dataType: 'text',
      type: 'POST',
      url: 's11.php',
      success: function(responseText) {
        $('#display').html(responseText);
      },
      failure: function() {
        alert("Failed");
      },
      error: function() {
        $('#display').html("Error");
      }
    });
  }

}


</script>


<body>
<form class="myform">
  <input type="text" name="username" placeholder="Username" class="a" id="x" required></input>
  <input type="password" name="password" placeholder="Password" class="a" id="y" required></input>
</form>
<button class="b" id="n" onclick="_submit()">Submit</button>

<div id="display"></div>
<p></p>
</body>