Filling a container with iterators from another container

Question

I have a std::map<int, int> and a std::list<std::map<int, int>::const_iterator>.

Can I use an STL-algorithm to fill the list with all the iterators from the map in order?
I don't want to use an explicit loop if possible.

You can't do this without a loop being involved. Even std::copy() uses a loop. — Galik
– Galik, Commented Nov 2, 2014 at 16:42
@Galik: Yes. I thought about nice written code. In one line using STL. I know that inside I need to use loop by I want to hide it. — peter55555
– peter55555, Commented Nov 2, 2014 at 16:44
I think I'd take a step back. Why, exactly, do you believe you need a std::list<map<int, int>::iterator>? This sounds highly suspect to me. — Jerry Coffin
– Jerry Coffin, Commented Nov 2, 2014 at 16:45

Columbo · Accepted Answer · 2014-11-02 16:56:51Z

The algorithms in the STL call functors with values, not with iterators. If you are obsessed with avoiding explicit loops then you might try to use iota with an iterator as a value:

list.resize(map.size()); std::iota( std::begin(list), std::end(list), std::begin(map) );

Demo.

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