I have heard of PROLOG but never seen it............where might I find the version that YOU USE?

Personally I would knock that up in Access or Excel or Lotus or FOXPRO

OK...................... SQLDB would be slightly more professional

Thirty years ago I could have written it in Fortran4 or Algol60.........but 80 column punched cards are no good these days

As a first shot try the "structured English" approach (OK ...structured Italian )

This is where you write programming instructions in simple language to say what processes you want to happen? That way you understand what is going to happen when you run it?

I am lazier than you........give me a link to PROLOG

Ciao