Deleting elements from a vector

Question

The following C++ code fills a vector with a number of objects and then removes some of these objects, but it looks like it deletes the wrong ones:

vector

        

Answer 1

You should work with stl::list in this case. Quoting the STL docs:

Lists have the important property that insertion and splicing do not invalidate iterators to list elements, and that even removal invalidates only the iterators that point to the elements that are removed.

So this would go along the lines of:

std::list photons;
photons = source->emitPhotons();
std::list::iterator i;
for(i=photons.begin();i!=photons.end();++i)
{
    bool useless=false;
    if(useless)
        photons.erase(i);
}