#include <iostream>
#include <vector>
#include <set>
using namespace std;

template <template<class...> class Container>
string pack_addrs(const Container<string>& caddrs) {
  string res;
  for (const string &addr : caddrs) {
    res += addr + ",";
  }
  return res.substr(0, res.size()-1);
}

int main() {
	vector<string> v{"one", "one", "two", "three"};
	cout << pack_addrs(v) << "\n";

	set<string> s{"one", "one", "two", "three"};
	cout << pack_addrs(s) << "\n";

	return 0;
}