Bus stops - 1

#include <iostream>
#include <string>
#include <map>
#include <set>
#include <vector>
#include <algorithm>

using namespace std;

//функция, проверяющая, есть ли в векторе определенная строка

bool FindVector (const vector <string>& a, const string& b) {
    for (const auto& m : a) {
        if (m == b) {
            return true;
        }

    }
    return false;
}


int main () {
    map <string, vector<string>> bus_to_stops;
    map <string, vector<string>> stop_to_buses;
    int Q;
    cin >> Q;
    for (int i = 0; i < Q; ++i) {
        string code;
        cin >> code;

        if (code == "NEW_BUS") {
            string bus;
            int stop_count;
            cin >> bus >> stop_count;
            for (int w = 0; w < stop_count; ++w) {
                string stop;
                cin >> stop;
                bus_to_stops[bus].push_back(stop);
                stop_to_buses[stop].push_back(bus);
            }
        }

        else if (code == "BUSES_FOR_STOP") {
            string stop;
            int th = 0;
            cin >> stop;
            for (const auto& x : bus_to_stops) {
                if (FindVector(x.second, stop) == 1) {
                    cout << x.first << " ";
                    th++;
                }
            }
            if (th == 0) {
                cout << "No stop";
            }
            cout << endl;
        }
        else if (code == "STOPS_FOR_BUS") {
            string bus;
            cin >> bus;
            if (bus_to_stops[bus].empty() == 1) {
                cout << "No bus" << endl;
                bus_to_stops.erase(bus);
            }
            else {
                for (const auto &t : bus_to_stops[bus]) {
                    cout << "Stop " << t << ": ";
                    if (stop_to_buses[t].size() == 1)
                        cout << "no interchange" << endl;
                    else {
                        for (const auto &u : stop_to_buses[t]) {
                            if (u != bus)
                                cout << u << " ";
                        }
                        cout << endl;
                    }
                }
            }

        }
        else if (code == "ALL_BUSES") {
            if (bus_to_stops.empty() == 1)
                cout << "No buses" << endl;
            else {
                for (const auto& x : bus_to_stops) {
                    cout << "Bus " << x.first << ": ";
                    for (const auto& r : x.second) {
                        cout << r << " ";
                    }
                    cout << endl;
                }
            }

        }
    }
    return 0;
}