using System;

public class Program

{

    public static void Main(){

        int n;

        Console.WriteLine("Input quantity of goods :");

        n = int.Parse(Console.ReadLine());

        hanghoa[] a = new hanghoa[100];

        for (int i=1;i <= n;i++){

        Console.WriteLine("Information of income goods{0}", i);

        a[i] = new hanghoa();

        a[i].nhap();

}

        Console.WriteLine("STT\tMAHANGHOA\tTENHANGHOA\tDONGIA\tSOLUONG");

        for (int i =1;i<= n;i++){

        Console.Write("{0}\t", i);

        a[i].xuat();

}

        Console.WriteLine("\n\nDANH SACH HANG HOA CAN NHAP VE LA :\n");

        Console.WriteLine("STT\tMAHANGHOA\tTENHANGHOA\tDONGIA\tSOLUONG");

        for (int i = 1; i <= n; i++){

        Console.Write("{0}\t", i);

        a[i].nhaphang();

}

        Console.ReadLine();

​

    }

}

public class hanghoa{

            string mahanghoa;

            string ten;

            float dongia ;

            int soluong;

            public void nhap(){

            Console.WriteLine("Input id of goods :");

            mahanghoa = Console.ReadLine();

            Console.WriteLine("Input kind of goods :");

            ten = Console.ReadLine();

            Console.WriteLine("Input price :");

            dongia = float.Parse(Console.ReadLine());

            Console.WriteLine("Input quantity :");

            soluong = int.Parse(Console.ReadLine());

}

            public void xuat(){

            Console.WriteLine("{0}\t\t{1}\t\t{2}\t\t{3}", mahanghoa,ten,dongia,soluong);

}

            public void nhaphang(){

            if (soluong<5)

            Console.WriteLine("{0}\t\t{1}\t\t{2}\t\t{3}", mahanghoa,ten,dongia,soluong);

    }

}

​