I have provided two versions of the assignment -- one in which
the top-level function MAIN uses exceptions and one in which it does not.
The corresponding files are  A4.ADA and A4EXCEPT.ADA.

    Because of the dependencies among the files, the suggested compilation
order is
             FUNDLS.ADB
             FUNDLS.ADA
             FUNCTS.ADB
             FUNCTS.ADA
             ENV.ADB
             ENV.ADA
             A4.ADA   or   A4EXCEPT.ADA

    The other files I gave you have been incorporated into these, rather
than being compiled separately.

                                JDS