Compilare: user.cpp: In function ‘int main()’: user.cpp:140:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < it.size(); ++ i) ^ user.cpp:153:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < biconnecteds.size(); ++ i) { ^ user.cpp:158:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < biconnecteds[i].size(); ++ j) ^ user.cpp:165:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= N + biconnecteds.size(); ++ i) ^