How can I copy one map into another using std::copy?

Question

I would like to copy the content of one std::map into another. Can I use std::copy for that? Obviously, the following code won\'t work:

int main         


        

Answer 1

You need a variant of an insert iterator:

std::copy(m1.begin(), m1.end(), std::inserter(m2, m2.end()) );

inserter is defined in <iterator>. It requires a place to insert into (hence the m2.end()), and returns an insert_iterator.

Answer 2

You can use GMan's answer --- but the question is, why do you want to use std::copy? You should use the member function std::map<k, v>::insert instead.

m2.insert(m1.begin(), m1.end());