name_sur

#include<iostream>
#include<map>
#include<string>
#include<vector>
using namespace std;
class Person {
private:
    map <int, string> surname;
    map<int, string> name;
public:
    void ChangeFirstName(int year, const string& first_name) {
      name[year] = first_name;/*add first name at year*/
    }
    void ChangeLastName(int year, const string& last_name) {
            surname[year] = last_name;
    }
    string GetFullName(const int& year) {
        // получить имя и фамилию по состоянию на конец года
        string finded_name, finded_surname;
        int temp_year = 0U;
        for (auto n : name) {
            if (n.first >= temp_year && n.first <= year) {
            finded_name = n.second;
            }
        }
        temp_year = 0U;
        for (auto s : surname) {
            if (s.first >= temp_year && s.first <= year) {
            finded_surname = s.second;
            }
        }
        if (finded_name != "" && finded_surname != "") {
            return finded_name+" "+finded_surname;
        }
        else if (finded_name != "" && finded_surname == "") {
            return finded_name+ " with unknown last name";
        }
        else if (finded_name == "" && finded_surname != "") {
            return finded_surname+" with unknown first name";
        }
        else {
            return "Incognito";
            }
        }
};
int main(void) {
    Person person;
    person.ChangeLastName(3, "3_2nd");
    person.ChangeLastName(6, "6_2nd");
    person.GetFullName(3);
    return 0;
}