using System;

public class Program

{

    public static void Main()

    {

        var val = 3;

        var res = (val > 0 ? val-1 : val) switch {

          0 => A(),

          1 => B(),

          _ => throw new Exception()

        };

        Console.WriteLine(res);

    }

    static string A() { return "A"; }

    static string B() { return "B"; }

}