static void Main(string[] args)
{
var dathuc_1 = new DaThuc(3);
dathuc_1.NhapDaThuc();
dathuc_1.XuatDaThuc();
var dathuc_2 = new DaThuc(3);
dathuc_2.NhapDaThuc();
dathuc_2.XuatDaThuc();
Console.WriteLine();
Console.WriteLine("Da thuc 1 + Da thuc 2 = ");
var dathuc_tong = dathuc_1 + dathuc_2;
dathuc_tong.XuatDaThuc();
var tong_2 = dathuc_1.Cong(dathuc_2);
tong_2.XuatDaThuc();
Console.WriteLine();
Console.WriteLine("Da thuc 1 - Da thuc 2 = ");
var dathuc_hieu = dathuc_1 - dathuc_2;
dathuc_hieu.XuatDaThuc();
var hieu_2 = dathuc_1.Tru(dathuc_2);
hieu_2.XuatDaThuc();
Console.ReadLine();
}
