using System;

public class Program

{

    public static TResult Timed<T1, /*T2, etc*/TResult>(out long duration, Func<T1, /*T2, etc*/TResult> func, T1 arg1/*T2 arg2, etc*/)

    {

        //start timing

        var t0 = DateTime.Now;

        var result = func(arg1);

        //end timing

        duration = (long)DateTime.Now.Subtract(t0).TotalMilliseconds;

        return result;

    }

    public int Factorial(int n)

    {

        return n > 0 ? n * Factorial(n - 1) : 1;

    }

    public int Fibonacci(int n)

    {

        return n > 1 ? Fibonacci(n - 2) + Fibonacci(n - 1) : n;

    }

    public static void Main()

    {

        var program = new Program();

        long duration;

        var _12bang = Timed(out duration, program.Factorial, 12);

        Console.WriteLine("{0}! = {1} in {2} ms", 12, _12bang, duration);

        var fib31 = Timed(out duration, program.Fibonacci, 31);

        Console.WriteLine("Fib {0} = {1} in {2} ms", 31, fib31, duration);

    }

}