#include <iostream>
#include <string>
#include <deque>
#include <set>
#include <boost/format.hpp>
#include <algorithm>

class foo {
        std::deque< std::set<std::string> > q;
public:
        void dump() {
                int cnt = 0;
                std::string res("");
                for ( std::deque<std::set<std::string> >::iterator i = q.begin();
                                i != q.end();
                                ++i, ++cnt ) {
                        res += (boost::format("Q%d[") % cnt).str();
                        for ( std::set<std::string>::iterator j = i->begin();
                                        j != i->end();
                                        ++j ) {
                                res += *j;
                                res += ", ";
                        }
                        res += "] ";
                }
                std::cout << "dump: " << res << "\n";
        }

        void add_set() {
                q.push_back(std::set<std::string>());
        }

        void add_str(std::string s) {
                q.back().insert(s);
        }

        void operator()(std::string s) {
                add_set();
                add_str(s);
        }
};

int main() {
        std::vector< std::string > v;
        foo f;

        v.push_back("string1");

        f.dump();

//      for_each(v.begin(), v.end(), f);
        for(std::vector< std::string >::iterator i = v.begin();
                        i != v.end();
                        ++i) {
                f(*i);
        }

        f.dump();
}