$(function() {

    $( "#menu" ).menu();

});

$( "#sortable" ).sortable();

$( "#sortable" ).disableSelection();

$( "li" ).draggable();

$( "#menu li" ).droppable({

    drop: function( event, ui ) {

        $( this )

            .appendTo( "#items" );

    }

});

$( "#items li" ).droppable({

    drop: function( event, ui ) {

        $( this )

            .appendTo( "#menu" );

    }

});