This is the computer science problem known for the traveling salesman who had to visit a number of cities at the lowest cost
.  It's been 20 years since I solved this in Pascal class, but I remember that you have to build a table with a cost for each pair of cities.  In your friend's case, it would be 14 by 14.  We assume that a trip from Chicago to Chicago costs $0.  The price from Chicago to New York may not be the same as the return trip.

In any event, I recall that the computation took a few seconds for the small matrix and ran for hours when you got above 12 cities.  Of course, today's GPS may have more computing power than the VAX of 1986.  

I don't expect any GPS will have software that will solve the big problem, but  will help make decisions on a case by case basis.  With driving, you have to choose if you want the shortest time by taking the freeway or the shortest distance which uses the slower streets and back roads.  When does the driver's wages exceed the price of gas?


Mark WB3CAI

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