static void Main(string[] args) { do { int n; n = SoNguyen.NhapSoNguyenDuong("Nhap n="); Console.Write("So luong chu so le cua " + n + " la " + TinhToan.dem(n)); } while (SoNguyen.NhapSoNguyen("\nTiep tuc (1.Tiep, 0.Khong)") != 0); }