static void Main(string[] args)
 {
     do
     {
         float a = SoThuc.NhapSoThuc("Nhap a = ");
         float b = SoThuc.NhapSoThuc("Nhap b = ");
         TinhToan.giapt(a, b);
     } while (SoNguyen.NhapSoNguyen("\nTiep tuc (1.Tiep, 0.Khong) ?") != 0);
 }