# Re: algorithm decomposition

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
comp.lang.c++.moderated
Date:
Fri, 9 Oct 2009 15:20:29 CST
Message-ID:
<hams13\$lv7\$1@news.eternal-september.org>
* Jun:

Hello all,

I tried to design a generic library for my working problem. But I've some
questions on how to decompose my algorithm, for example:

A generic algorithm, try to generate the weight on each element
class AlgorithmWeight{
void solve(InputIterator first, InputIterator last){
generateWeight(first, last)
// traveling all the element
while(first != last){
if(verify(first))
++first;
}

// orderByWeight(first, last);

}
};

The weighting system is only used in algorithmWeight which has no direct
influence with another algorithm. How can I decompose weight from elements.

It's unclear what you mean.

The code you've shown is not sufficient.

Here's a possible implementation of 'addWeight':

void addWeight( InputIterator const it )
{
++weights[&*it];
}

where 'weights' is e.g. a 'std::map<T*,int>'.

I've a preliminary thought that :
I create a Policy template called weight, I combine my element class with this
weight template.

template <typename WeightPolicy>
class Element : public WeightPolicy{
using WeightPolicy:weightRelatedOprs; ....
}

Huh?

Any better solution ?

What is the question?

Please provide a more detailed description & example.

Cheers & hth.,

- Alf

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