Use the Menu Revision feature to view and compare the menu revisions you have made previously. This helps you to switch back to an earlier revision made as per your needs.
To do so, check the Start Revision box for the menu you want to view a history of revisions made.
Once you make a revision in your menu, you can compare the revisions as shown here. You can view the revision according to date and time. There is also the option to delete and restore revisions made.
The revision feature clearly shows the pages you have deleted and the ones you have dragged and dropped to make child items.