My own accounting python euler problem

[Ozz]

Robert P. J. Day schreef:
>   does your solution allow for the possibility of different invoices
> of equal amounts?  i would be reluctant to use the word "subset" in a
> context where you can have more than one element with the same value.

I think it handles different invoices of equal amounts correctly.
I agree with you though that the term subset may not be the best name in 
this context because of those duplicates.

cheers,
Ozz