The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <iostream>
#include <unordered_set>
#include <vector>
#include <algorithm>
#include "print.hpp"
#include "assoiter.hpp"
int main()
{
std::unordered_set<int> coll;
// create inserter for coll
// - inconvenient way
asso_insert_iterator<decltype(coll)> iter(coll);
// insert elements with the usual iterator interface
*iter = 1;
iter++;
*iter = 2;
iter++;
*iter = 3;
PRINT_ELEMENTS(coll);
// create inserter for coll and insert elements
// - convenient way
asso_inserter(coll) = 44;
asso_inserter(coll) = 55;
PRINT_ELEMENTS(coll);
// use inserter with an algorithm
std::vector<int> vals = { 33, 67, -4, 13, 5, 2 };
std::copy (vals.begin(), vals.end(), // source
asso_inserter(coll)); // destination
PRINT_ELEMENTS(coll);
}