# Re: how many combinations in a list equal a certain total

 Subject: Re: how many combinations in a list equal a certain total Posted by: Tom Ogilvy (twogil…@msn.com) Date: Thu, 30 Oct 2003

There are 2^480 - 1  unique combinations to check.  As a point of
comparison, there are only 8,640,000 seconds in 100 years (slightly larger
then 2^23)  In otherwords, there isn't enough time to do an exhaustive
examination without even trying to look at the results.

You could come up with a list of Unique prices and reduce the number of rows
you need to examine.  (so in your example, any solution that contains a B
could be another solution by replacing B with F)

Regards,
Tom Ogilvy

"Sherrie" <sb66…@sbc.com> wrote in message
news:et9k5NwnDHA.20…@TK2MSFTNGP09.phx.gbl...
> I have a list of 479 rows. Column A is a product name, column B is cost. I
> need to come up with every possible combination of pruducts that equals
> \$100.
>
> For instance:
> Product A    \$100
> Product B    \$50
> Product C    \$38.72
> Product D    \$20
> Product E    \$30
> Product F    \$50
>
> A
> B+D+E
> B+F
> F+E+D
>
> Each Product can be used only once so B+B wouldn't work.
>