immediately invoked lambda expression

#include <algorithm>
#include <iostream>
#include <functional>
#include <map>
#include <unordered_map>
#include <numeric>
#include <set>
#include <string>
#include <vector>


using namespace std;


struct Person {
    string name;
    int age, income;
    bool is_male;
};


struct PreCalculatedInfo
{

    std::vector<int> age_set;
    std::vector<int> wealth_set;

    std::vector<int> wealth_precalculated;
    std::vector<int> age_precalculated;

    std::unordered_map<std::string_view, int> women_names;
    std::unordered_map<std::string_view, int> men_names;


    std::string popular_man_name;
    std::string popular_woman_name;
};


const PreCalculatedInfo Precalculate(std::vector<Person> people)
{
    PreCalculatedInfo result;

    int popular_woman_name_counter = 0;
    int popular_man_name_counter = 0;

    //запоминаем самых популярных людей мужского и женского пола
    for(const auto& it : people)
    {
        result.wealth_set.push_back(it.income);
        result.age_set.push_back(it.age);

        // (it.is_male) ? result.men_names[it.name]++ : result.women_names[it.name]++;
        if(it.is_male)
        {
            result.men_names[it.name]++;

            if(result.men_names[it.name] > popular_man_name_counter)
            {
                popular_man_name_counter++;
                result.popular_man_name = it.name;
            }
        }
        else
        {
            result.women_names[it.name]++;

            if(result.women_names[it.name] > popular_woman_name_counter)
            {
                popular_woman_name_counter++;
                result.popular_woman_name = it.name;
            }
        }
    }

    //упорядочиваем векторы по возрастанию для age и убыванию для wealth
    std::sort(result.age_set.begin(), result.age_set.end());
    std::sort(result.wealth_set.begin(), result.wealth_set.end(), [](const int& lhs, const int& rhs){return lhs >= rhs;});

    //вычисляем значения богатства для запроса WEALTH
    result.wealth_precalculated.reserve(result.wealth_set.size()+1);
    result.wealth_precalculated[0] = 0;
    size_t counter = 1;
    for(const auto& it : result.wealth_set)
    {
        result.wealth_precalculated[counter] = result.wealth_precalculated[counter-1] + it;
        counter++;
    }

    //вычисляем значения совершеннолетних для запроса AGE
    size_t max_age = result.age_set[result.age_set.size()-1];
    result.age_precalculated.reserve(max_age+1);
    for(size_t i = 0; i <= max_age; i++ )
    {
        auto adult_begin = lower_bound(result.age_set.begin(), result.age_set.end(), i);
        result.age_precalculated[i] = distance(adult_begin, result.age_set.end());
    }

    return result;
}


const vector<Person> ReadPeople(istream& input) {
    int count;
    input >> count;

    vector<Person> result(count);
    for (Person& p : result) {
        char gender;
        input >> p.name >> p.age >> p.income >> gender;
        p.is_male = gender == 'M';
    }

    return result;
}

int main()
{

    //вызов через функцию
    //const PreCalculatedInfo pre_calc_info = Precalculate(ReadPeople(cin));

    const vector<Person> people = ReadPeople(cin);
    //вызов через лямбду
    const PreCalculatedInfo pre_calc_info = std::invoke([&people]{
            PreCalculatedInfo result;

            int popular_woman_name_counter = 0;
            int popular_man_name_counter = 0;

            //запоминаем самых популярных людей мужского и женского пола
            for(const auto& it : people)
            {
                result.wealth_set.push_back(it.income);
                result.age_set.push_back(it.age);

                // (it.is_male) ? result.men_names[it.name]++ : result.women_names[it.name]++;
                if(it.is_male)
                {
                    result.men_names[it.name]++;

                    if(result.men_names[it.name] > popular_man_name_counter)
                    {
                        popular_man_name_counter++;
                        result.popular_man_name = it.name;
                    }
                }
                else
                {
                    result.women_names[it.name]++;

                    if(result.women_names[it.name] > popular_woman_name_counter)
                    {
                        popular_woman_name_counter++;
                        result.popular_woman_name = it.name;
                    }
                }
            }

            //упорядочиваем векторы по возрастанию для age и убыванию для wealth
            std::sort(result.age_set.begin(), result.age_set.end());
            std::sort(result.wealth_set.begin(), result.wealth_set.end(), [](const int& lhs, const int& rhs){return lhs >= rhs;});

            //вычисляем значения богатства для запроса WEALTH
            result.wealth_precalculated.reserve(result.wealth_set.size()+1);
            result.wealth_precalculated[0] = 0;
            size_t counter = 1;
            for(const auto& it : result.wealth_set)
            {
                result.wealth_precalculated[counter] = result.wealth_precalculated[counter-1] + it;
                counter++;
            }

            //вычисляем значения совершеннолетних для запроса AGE
            size_t max_age = result.age_set[result.age_set.size()-1];
            result.age_precalculated.reserve(max_age+1);
            for(size_t i = 0; i <= max_age; i++ )
            {
                auto adult_begin = lower_bound(result.age_set.begin(), result.age_set.end(), i);
                result.age_precalculated[i] = distance(adult_begin, result.age_set.end());
            }

            return result;

    });

    for (string command; cin >> command;)
    {
        if (command == "AGE"s)
        {
            int adult_age;
            cin >> adult_age;

            //auto adult_begin = lower_bound(pre_calc_info.age_set.begin(), pre_calc_info.age_set.end(), adult_age);

            cout << "There are "s << pre_calc_info.age_precalculated[adult_age] << " adult people for maturity age "s
                 << adult_age << '\n';
        }
        else if (command == "WEALTHY"s)
        {
            int count;
            cin >> count;
            cout << "Top-"s << count << " people have total income "s << pre_calc_info.wealth_precalculated[count] << '\n';
        }
        else if (command == "POPULAR_NAME"s)
        {
            char gender;
            cin >> gender;

            if(gender == 'M' && pre_calc_info.men_names.size() == 0)
            {
                cout << "No people of gender "s << gender << '\n';
            }
            else if (gender == 'M' && pre_calc_info.men_names.size() > 0)
            {
                cout << "Most popular name among people of gender "s << gender << " is "s << pre_calc_info.popular_man_name << '\n';
            }
            else if(gender == 'W' && pre_calc_info.women_names.size() == 0)
            {
                cout << "No people of gender "s << gender << '\n';
            }
            else if(gender == 'W' && pre_calc_info.women_names.size() > 0)
            {
                cout << "Most popular name among people of gender "s << gender << " is "s << pre_calc_info.popular_woman_name << '\n';
            }

        }
    }
}