using System.Runtime.CompilerServices;

namespace StringCountExtention
{
    internal class Program
    {
        static void Main(string[] args)
        {
            string input = "Hello World!";
            Console.WriteLine($"{input.LeftStringCount(5)}");
            Console.WriteLine($"{input.RightStringCount(6)}");
        }
    }
    static class StringCountExtention
    {
        public static string LeftStringCount(this string input, int frqen)
        {
            return input.Substring(0, frqen);
        }
        public static string RightStringCount(this string input, int frqen)
        {
            return input.Substring(frqen);
        }
    }

}