jquery replicate div on drag

1$('.draggable').draggable({
2  revert: "invalid",
3  stack: ".draggable",
4  helper: 'clone'
5});
6$('.droppable').droppable({
7  accept: ".draggable",
8  drop: function(event, ui) {
9    var droppable = $(this);
10    var draggable = ui.draggable;
11    // Move draggable into droppable
12    var drag = $('.droppable').has(ui.draggable).length ? draggable : draggable.clone().draggable({
13      revert: "invalid",
14      stack: ".draggable",
15      helper: 'clone'
16    });
17    drag.appendTo(droppable);
18    draggable.css({
19      float: 'left'
20    });
21  }
22});