How can I turn a list of Aliases into a menu structure? I'm in a massive migration from a home grown CMS. So far I've been successful at using Feed Import to slurp in CSV exports of the old MySQL database. The old database contained page URLs. So I just mapped this over to Page Alias!

Now I'm searching for a more automated way to take this

/program/science/thesis
/program/math/core_requirements
/program/science/projects
/program/literature/great_works_collection
/program/literature/great_authors_showcase


into a menu structure like this: 

Navigation Menu 
+- Program 
  +-science
    +-thesis
    +-projects
  +-math
    +-core_requirements
  +-literature
    +-great_works_collection
    +-great_authors_showcase


Yes, I could do this manually, but I have over two thousand imported pages.

Is there an Alias URL to Menu structure script or module that may help me along?

Update:

Based on feedback below, I decided to pull a list of URLs from the CSV file using the following pipe line. That is, I pulled only 5th column (the URLs), sorted the output, filtered urls that had "/programs/", and cut off the trailing quote

awk -F ',"' '{print $5}' programs.csv | sort | grep programs | sed "s/\"//g"


After that was exported to a file, a ran the following to generate the child items of the menu:

cat programs.just.urls.txt | awk -F '/' '{print $3}' | egrep -v "php$" | uniq
I'd give the Menu Export/Import module a go.


  This module helps to export and/or import menus. Using it you can
  easily copy menus from one Drupal site to another.
  
  It also allows developers to quickly build a new Drupal site by
  creating empty content and menu items referencing it. The module may
  be used in ensemble with Node export that allows to add content to
  your Drupal site. In this case, menu import allows to batch-arrange
  existing content into a given menu structure, using a very simple text
  file.


I guess you could possibly use Excel or something to take your list of aliases and split the paths to columns which would give you the menu title (in the last column of the split).

From there you have the menu link titles and paths, so it's just a case of getting it into the format that the module expects.