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                    // Merge building addresses
                    for (size_t i = 0; i < local.building_addrs.size(); i++) {
                        auto& s = local.interned_strings[str_idx++];
                        auto sep = s.find('\0');
                        std::string hn = s.substr(0, sep);
                        std::string st = s.substr(sep + 1);

                    // Merge building addresses
                    for (size_t i = 0; i < local.building_addrs.size(); i++) {
                        auto& s = local.addr_strings[i];
                        auto sep = s.find('\0');
                        std::string hn = s.substr(0, sep);
                        std::string st = s.substr(sep + 1);