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Re: Looking for simple brute force solution

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On 1/4/18 5:14 AM, root wrote:
> cost of materials 100.
> cost of assembly   45.
> cost of item      145.
> cost of shipping   11.
> total cost        156.
> 
> 
> In this list it is easy to see that we can take the
> first, second, and fourth items to account for the total
> cost. We have to ignore the intermediate term 145.

It sounds like your goal is to transform that list into something like;


         100   Cost of materials
          45   Cost of Assembly
     145      Cost of Item
      11      Cost of Shipping
156         Total Cost

Where you assign everything a 'level' (the grand sum being level 0) and 
a given level is the sum of all the items 1 level higher between it and 
the previous item of its level. It sounds like you also want to allow 
some items to be negated for the sum, as credits/debits aren't carefully 
indicated (which actually make the process much tougher). If at all 
possible, I would try to understand the category names and assign a sign 
to them, even if I had to try a couple possibilities, as only having 
sums and no differences makes things much simpler.

Now if 'running sums' aren't actually right after the items they are the 
sum for, then you probably need to brute force the solution.

IF you can try assigning signs to values to make it so you are always 
adding, then you can work starting at the top of the list with the 
second item (as the first can't be a running sum) and see if that item 
is the sum of some number of items before it that aren't part of a 
previously detected running sum, and if you find such a case, mark it as 
a running sum, and push everything that went into it up a level (and 
things that made them up a level too).

Note, this means that Cost of Shipping would only check if it was 'sum 
of Cost of Item, and not include Cost of Assembly, as this is already 
accounted for.

There is a chance that you may miss-detect some running sums if the 
numbers aren't accurate or just happen to add up, and for a one-off, 
just outputting that detection may be enough (or even do it by hand, as 
the human brain is better at detecting suspicious conditions) for you to 
manually adjust things.

If you really need to do it programmatically, you can add back tracking 
where you systematically undo marking things as possible running sums 
until you get to a suitable result.

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Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-03 23:18 +0000
  Re: Looking for simple brute force solution fir <profesor.fir@gmail.com> - 2018-01-03 16:49 -0800
    Re: Looking for simple brute force solution fir <profesor.fir@gmail.com> - 2018-01-03 17:11 -0800
      Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 10:14 +0000
        Re: Looking for simple brute force solution Richard Damon <Richard@Damon-Family.org> - 2018-01-04 10:52 -0500
          Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 16:46 +0000
            Re: Looking for simple brute force solution Richard Damon <Richard@Damon-Family.org> - 2018-01-04 12:37 -0500
  Re: Looking for simple brute force solution Richard Damon <Richard@Damon-Family.org> - 2018-01-03 21:28 -0500
    Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 09:42 +0000
      Re: Looking for simple brute force solution Richard Damon <Richard@Damon-Family.org> - 2018-01-04 10:16 -0500
        Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 17:26 +0000
          Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 21:19 +0000
  Re: Looking for simple brute force solution Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-01-04 02:29 +0000
    Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 09:55 +0000
      Re: Looking for simple brute force solution Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-01-04 14:29 +0000
        Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 16:55 +0000
          Re: Looking for simple brute force solution Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-01-04 20:36 +0000
      Re: Looking for simple brute force solution Robert Wessel <robertwessel2@yahoo.com> - 2018-01-04 12:03 -0600
        Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 21:28 +0000
          Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 21:50 +0000
            Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-04 23:06 +0000
            Re: Looking for simple brute force solution Richard Damon <Richard@Damon-Family.org> - 2018-01-04 21:35 -0500
              Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-05 05:59 +0000
                Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-05 16:48 +0000
                Re: Looking for simple brute force solution Richard Damon <Richard@Damon-Family.org> - 2018-01-06 08:50 -0500
                Re: Looking for simple brute force solution root <NoEMail@home.org> - 2018-01-06 16:47 +0000

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