using System;

public class Program

{

    public static void Main()

    {

        int[] acct = new int[3];

​

        acct[0] = 8675309;

        acct[1] = 8675310;

        acct[2] = 8675311;

​

        int myacct = 8675311;

​

        switch (myacct)

        {

            case int a when a == acct[0]:

                Console.WriteLine("0");

                break;

​

            case int a when a == acct[1]:

                Console.WriteLine("1");

                break;

​

            case int a when a == acct[2]:

                Console.WriteLine("2");

                break;

​

            default:

                Console.WriteLine("default");

                break;

        }

    }

}