churras c++

#include <bits/stdc++.h>

using namespace std;

map <string, vector<string> > grafo;
vector<string> resp;
int cases, num;

void bfs(string no){
    queue<pair<string, int> > q;
    map<string, bool> vis;
    vis[no] = true;

    for(int i = 0; i < grafo[no].size(); i++) q.push(make_pair(grafo[no][i], 1));

    while (!q.empty()){
        pair<string, int> top = q.front();
        q.pop();

        vis[top.first] = true;
        if(top.second <= num) resp.push_back(top.first);

        for(int i = 0; i <= grafo[top.first].size(); i++){
            if(!vis[grafo[top.first][i]]){
                vis[grafo[top.first][i]] = true;
                q.push(make_pair(grafo[top.first][i], top.second + 1));
            }
        }
    }
}

int main(){
    cin >> cases >> num;
    string nome, amigo;
    for(int i = 0; i < cases; i++){
        cin >> nome >> amigo;
        grafo[nome].push_back(amigo);
        grafo[amigo].push_back(nome);
    }
    bfs("Rerisson");
    cout << resp.size() << endl;
    for(int i = 0; i < resp.size(); i++) cout << resp[i] << endl;
    return 0;
}