jQuery Konami trigger that doesn't accumulate a large array of chars

knmi.js

  var kkeys = [];
  var konami = "38,38,40,40,37,39,37,39,66,65";
  
  $(document).on('keydown',
    function(e) {
      kkeys.push( e.keyCode );
      kkeys=kkeys.slice(-10);
      if ( kkeys.toString().indexOf(konami) >= 0 ){
        $(document).off('keydown');
        kkeys = [];

        alert('KONAMI!');

      }
    }
  );