using System;

using System.Collections.Generic;

​

​

// example for Open and closed principle

// Adding savings and current  and one more category

​

​

public class Program

{

public void Main()

{

    int choice;

    Console.WriteLine("Enter 1 to add savings and 2 to add current");

    choice = Convert.ToInt16(Console.ReadLine());

    switch(choice)

    {

    case 1:

        AddSavingsaccount A = new AddSavingsaccount();

        int result1=    A.add();

    if(result1==1)

    {

    Console.WriteLine("list of students added sucessfully");

​

    }

        break;

        case 2:

                AddCurrentaccount B = new AddCurrentaccount();

             int result2 =  B.add();

    if(result2==1)

    {

    Console.WriteLine("list of students added sucessfully");

​

    }

​

        break;

    }

}

​

​

}

public interface ICategory

{

int add();

}

​

​

public class AddSavingsaccount:ICategory

{

    string name;

 int i;

    List<string> listsavingsacc= new List<string>();

public int add()

{ 

    Console.WriteLine("Give no of savingsaccounts you are adding");

 int c= Convert.ToInt16(Console.ReadLine());

 for(i=1;i<=c;i++)

 {

​

 Console.WriteLine("Enter  name"+i);

 name = Console.ReadLine();

 listsavingsacc.Add(name);

 }

return 1;

}

}

​

​

​

public class AddCurrentaccount:ICategory

{

    string name;

 int i;

    List<string> listcurrentacc= new List<string>();

public int add()

{ 

    Console.WriteLine("Give no of currentaccounts you are adding");

 int c= Convert.ToInt16(Console.ReadLine());

 for(i=0;i<c;i++)

 {

​

 Console.WriteLine("Enter  name");

 name = Console.ReadLine();

 listcurrentacc.Add(name);

 }

return 1;

}

}