Uncaught TypeError: $ is not a function

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.9/jquery.validate.js"></script>

    <script src="https://code.jquery.com/jquery-3.1.1.min.js" integrity="sha384-3ceskX3iaEnIogmQchP8opvBy3Mi7Ce34nWjpBIwVTHfGYWQS9jwHDVRnpKKHJg7" crossorigin="anonymous"></script>

jQuery(document).ready(function($){

    // jQuery code is in here

});

<script src='jquery.js'></script>    
if (typeof $ == 'undefined') {
   var $ = jQuery;
}

(function($){

  $(document).ready(function(){
      // write code here
  });

  // or also you can write jquery code like this

  jQuery(document).ready(function(){
      // write code here
  });

})(jQuery);

(function ($) {
   $(document).
}(jQuery));