void bfs(int v) {
    queue<int> q;
    q.push(v);
    used[v] = 1;
    while (q.size != 0) {
        for (int i = 1; i <= n; i++) {
            if (used[i] == 0 && mas[v][i] == 1) {
                q.push(i);
                used[i] = 1;
            }
        }
        q.pop();
        bfs(q.front());
    }
}