struct Edge {
  int src, dest;
};
class Graph {
public:
  vector<vector<int>> adjList;
  Graph(vector<Edge> const &edges, int n) {
    adjList.resize(n);
    for (auto &edge : edges) {
      adjList[edge.src].push_back(edge.dest);
      adjList[edge.dest].push_back(edge.src);
    }
  }
};
void BFS(Graph const &graph, int v, vector<bool> &discovered) {
  queue<int> q;
  discovered[v] = true;
  q.push(v);
  while (!q.empty()) {
    v = q.front();
    q.pop();
    cout << v << " ";
    for (int u : graph.adjList[v]) {
      if (!discovered[u]) {
        discovered[u] = true;
        q.push(u);
      }
    }
  }
}