Compilare: user.cpp: In function ‘void Cross()’: user.cpp:64:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < V[nod].size(); ++i) ^ user.cpp:77:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i <f.size(); ++i) ^ user.cpp:80:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < V[f[i]].size(); ++j) ^ user.cpp:88:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < s.size(); ++j) ^