#include <iostream>
#include <cmath>
#include <set>
#include <utility>
#include <vector>
#include <map>
#include <algorithm>
#include <iomanip>
#include <cctype>

std::string FindNameByYear(const std::map <int, std::string>& names, int year) {
    std::string ans;
    if (!names.empty()) {
        if (year >= names.begin() -> first) {
            auto it1 = names.upper_bound(year);
            ans =  (--it1) -> second;
        }
    }
    return ans;
}

std::string HistoryOfNames(const std::map <int, std::string>& names, int year) {
    std::string ans;
    if (!names.empty()) {
        std::vector<std::string> buff;
        auto it_now = --names.upper_bound(year);
        int now_year = (--names.upper_bound(year))->first;
        std::string tmp;
        ans += " (";
        for (auto it = names.begin(); it != it_now; ++it) {
            if (it -> second != tmp) {
                ans += it -> second;
                ans += ", ";
                tmp = it -> second;
            }
        }
        ans += ") ";
    }
    return ans;
}

class Person {
public:
    void ChangeFirstName(int year, const std::string& first_name) {
        first_names[year] = first_name;
    }
    void ChangeLastName(int year, const std::string& last_name) {
        last_names[year] = last_name;
    }
    std::string GetFullName(int year) {
        std::string first_name = FindNameByYear(first_names, year);
        std::string last_name = FindNameByYear(last_names, year);

        if (first_name.empty() && last_name.empty()) return "Incognito";
        else {
            if (first_name.empty()) return last_name + " with unknown first name";
            if (last_name.empty()) return first_name + " with unknown last name";
            return first_name + " " + last_name;
        }

        // получить имя и фамилию по состоянию на конец года year
    }
    std::string GetFullNameWithHistory(int year) {
        std::string first_name_now = FindNameByYear(first_names, year);
        std::string last_name_now = FindNameByYear(last_names, year);
        std::string first_name_history = HistoryOfNames (first_names, year);
        std::string last_name_history = HistoryOfNames (last_names, year);

        if (first_name_now.empty() && last_name_now.empty()) return "Incognito";
        else {
            if (first_name_now.empty()) return last_name_now + last_name_history + " with unknown first name";
            if (last_name_now.empty()) return first_name_now + first_name_history + " with unknown last name";
            return first_name_now + first_name_history + " " + last_name_now + last_name_history;
        }

        // получить все имена и фамилии по состоянию на конец года year
    }

private:
    std::map <int, std::string> first_names;
    std::map <int, std::string> last_names;
    // приватные поля
};


int main() {
    Person person;

    person.ChangeFirstName(1900, "Eugene");
    person.ChangeLastName(1900, "Sokolov");
    person.ChangeLastName(1910, "Sokolov");
    person.ChangeFirstName(1920, "Evgeny");
    person.ChangeLastName(1930, "Sokolov");
    std::cout << person.GetFullNameWithHistory(1940) << std::endl;

    return 0;
}