using System;

public class Program

{

    //static T f<T>(T a)

    //{

        //switch (a)       // 1st way

        //{

            //case int aint:

            //  return (T)(object)(aint*10);

            //case double adouble:

            //  return (T)(object)(adouble/10);

            //default:

                //return (T)(object)(null);

    //  }

        //T t=a switch    // 2nd way

        //{

        //  int aint=>(T)(object)(aint*10),

            //  double adouble=> (T)(object)(adouble/10),

                //_=>(T)(object)(null)

        //};

        //return t;

        //return a switch    // 3rd way

        //{

        //  int aint=>(T)(object)(aint*10),

            //  double adouble=> (T)(object)(adouble/10),

                //_=>(T)(object)(null)

    //  };

        //return (T)(object)("hi");

        //}

        static T f<T>(T a)=> a switch    // 4th way

        {

            int aint=>(T)(object)(aint*10),

                double adouble=> (T)(object)(adouble/10),

                _=>(T)(object)(null)

        };

    public static void Main()

    {

        Console.WriteLine(f(123));

        Console.WriteLine(f(1.23));

        Console.WriteLine(f("ali"));

    }

}