I'm creating a JQuery puzzel game, how can I check if a draggable piece was not dropped on a droppable. I want to increment Incorrect meves if the piece was revert to its original position.

 

This is what I have done

 

$("#PUZ01").draggable({ revert: 'invalid', helper:'original', opacity: 0.5, containment: 'div#DIV', cursor: 'hand'});
  
  $("#POS01").droppable({
   accept: "#PUZ01",
   tolerance: 'intersect',
   drop: function() {
   $('#POS01').addClass('POS01');
   Counter++;
   $('#PUZ01').remove();
   CorrectMove();
   checkWin();

}

});