Compilare: user.cpp: In function ‘void Read()’: user.cpp:54:23: warning: narrowing conversion of ‘std::sqrt<int>(N)’ from ‘__gnu_cxx::__enable_if<true, double>::__type {aka double}’ to ‘int’ inside { } [-Wnarrowing] int x, y, r{sqrt(N)}; ^ user.cpp: In function ‘void Solve()’: user.cpp:89:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( j = 1; j < G[i].size(); ++j ) ^ user.cpp:69:15: warning: ‘k’ may be used uninitialized in this function [-Wmaybe-uninitialized] int i, j, k; ^