#include <set>
#include <vector>
#include <iostream>

using namespace std;

template <typename RandomIt>
pair<RandomIt, RandomIt> FindStartsWith(RandomIt range_begin, RandomIt range_end, char prefix) {
    RandomIt it_begin, it_end;
    bool flag = false;
    bool check = false;

    for (auto it = range_begin; it < range_end; ++it) {
        if (*((*it).begin()) == prefix && !flag) {
            it_begin = it;
            flag = true;
        }
        if (*((*it).begin()) != prefix && flag) {
            it_end = prev(it);
            flag = false;
            check = true;
        }
    }
    if (check) {
        return make_pair(it_begin, it_end);
    }
    else {
        if ((int)prefix <= (int)(*((*range_begin).begin()))) {
            cout << (int)prefix << " "s << (int)(*((*range_begin).begin())) << endl;
            return make_pair(next(range_begin), next(range_begin));
        }

        if ((int)prefix >= (int)(*((*range_end).begin()))) {
            cout << (int)prefix << " "s << (int)(*((*range_end).begin())) << endl;
            return make_pair(prev(range_end), prev(range_end));
        }

        for (auto it = range_begin; it < range_end; ++it) {
            if ((int)prefix < (int)(*((*(it + 1)).begin())) &&
                (int)prefix >(int)(*((*(it)).begin()))) {
                cout << (int)(*((*it).begin())) << " "s << (int)prefix << " "s << (int)(*((*(it + 1)).begin())) << endl;
                return make_pair(next(it), next(it));
            }
        }
    }
}

int main() {
    const vector<string> sorted_strings = { "moscow", "murmansk", "vologda", "vorohesh"};
    const auto m_result = FindStartsWith(begin(sorted_strings), end(sorted_strings), 'm');
    for (auto it = m_result.first; it <= m_result.second; ++it) {
        cout << *it << " ";
    }
    cout << endl;
    const auto a_result = FindStartsWith(begin(sorted_strings), end(sorted_strings), 'p');
    cout << (a_result.first - begin(sorted_strings)) << " " << (a_result.second - begin(sorted_strings)) << endl;

    const auto p_result = FindStartsWith(begin(sorted_strings), end(sorted_strings), 'a');
    cout << (p_result.first - begin(sorted_strings)) << " " << (p_result.second - begin(sorted_strings)) << endl;

    const auto z_result = FindStartsWith(begin(sorted_strings), end(sorted_strings), 'z');
    cout << (z_result.first - begin(sorted_strings)) << " " << (z_result.second - begin(sorted_strings)) << endl;
    return 0;
}