using System;

class Customer

{

    protected int CustId;

    protected string CustName;

    public Customer(int c, string d)

    {

        this.CustId=c;

        this.CustName=d;

    }

    public int custId

    { 

        get{return CustId;} 

        set{CustId=value;}

    }

    public string custName

    { 

        get{return CustName;} 

        set{CustName=value;}

    }

    public void Display()

    {

        Console.WriteLine(CustId+"\n"+CustName);

    }

}

​

class RegularCustomer:Customer

{

    private string payment;

    public RegularCustomer(int c, string d, string p): base(c,d)

    {

       payment=p;

    }

    public void DisplayPayment()

    {

    Console.WriteLine(payment);

    }

}

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Enter the Customer ID, Customer Name and the Payment");

        int c=Convert.ToInt32(Console.ReadLine());

        string d=Console.ReadLine();

        int i=0;

        while(i!=1)

        {

        string e=Console.ReadLine();

        e=e.ToLower();

        if(e=="credit"||e=="cash")

        {

        RegularCustomer r=new RegularCustomer(c,d,e);

        r.Display();

        r.DisplayPayment();

        i+=1;

        }

        else

        Console.WriteLine("Enter the correct Payment (credit/cash)");

        }

    }

}

​