Compilare: user.cpp: In function ‘int main()’: user.cpp:63:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (flag == 0 && j < hop[i].size()) { ^ user.cpp:79:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size(); i++) ^