Compilare: user.cpp: In function ‘void Write(std::ofstream&)’: user.cpp:16: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void DFS(int)’: user.cpp:58: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void Solve()’: user.cpp:65: warning: unused variable ‘j’ user.cpp:65: warning: unused variable ‘last’ user.cpp:65: warning: unused variable ‘nr’ user.cpp:65: warning: unused variable ‘v’