append set to another set

Question

Is there a better way of appending a set to another set than iterating through each element ?

i have :

set foo ;
set bar          


        

Answer 1

It is not a more efficient but less code.

bar.insert(foo.begin(), foo.end());

Or take the union which deals efficiently with duplicates. (if applicable)

set<string> baz ;

set_union(foo.begin(), foo.end(),
      bar.begin(), bar.end(),
      inserter(baz, baz.begin()));

Answer 2

You can insert a range:

bar.insert(foo.begin(), foo.end());