Write a C# Sharp program to convert the last 3 characters of a given string in upper case. If the length of the string has less than 3 then uppercase all the characters

using System;
namespace exercises
{
   class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(test("Python"));
            Console.WriteLine(test("Javascript"));
            Console.WriteLine(test("js"));
            Console.WriteLine(test("PHP"));
            Console.ReadLine();
        }
     public static string test(string str)
        {
            return str.Length < 3 ? str.ToUpper() : str.Remove(str.Length - 3) + str.Substring(str.Length - 3).ToUpper();
        }
  }
}