#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;
}

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