Compilare: user.cpp: In function ‘void bf()’: user.cpp:50:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[node].size();++i) ^ user.cpp:61:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[node].size();++i) ^ user.cpp:66:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[node].size();++i) ^ user.cpp: In function ‘void write()’: user.cpp:82:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sol.size();++i) ^