Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:19:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[nod].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:59:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < c[i].size(); ++j) ^