lab 6 z 12 csharp

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace lab_6_z_12_csharp
{
    interface Ix
    {
        string F0(int n);
        void F1(int n2);
    }

    interface Iy
    {
        void F0(int n, out string s);
        void F1(int n2);
    }
    public class Cl1 : Ix, Iy
    {
        public string str1;
        public Cl1() { }
        public Cl1(string st)
        {
            this.str1 = st;
        }
        public string F0(int n)
        {
            //Console.WriteLine("From class 1, interface Ix");
            string s = this.str1;
            char ch = s[n];
            string s2 = Convert.ToString(ch);
            s = s.Replace(s2, "+");
            return s;
        }
        void Ix.F1(int n2)
        {
            Console.WriteLine("From class 1, interface Ix");
            char ch = this.str1[n2];
            string s = Convert.ToString(ch);
            this.str1 = this.str1.Replace(s, "+");
        }

        public void F0(int n, out string s)
        {
            s = this.str1;
            char ch = s[n];
            string s2 = Convert.ToString(ch);
            s = s.Replace(s2, "+");
        }

        void Iy.F1(int n)
        {
            Console.WriteLine("From class 1, interface Iy");
            char ch = this.str1[n];
            string s = Convert.ToString(ch);
            this.str1=this.str1.Replace(s, "+");
        }

    }

    class Cl2 : Ix, Iy
    {
        public string str2;
        public Cl2() { }
        public Cl2(string st)
        {
            this.str2 = st;
        }

        public string F0(int n)
        {
            //Console.WriteLine("From class 2, interface Ix");
            string s1 = string.Copy(str2);
            s1 = s1.Substring(n);
            return s1;
        }
        public void F1(int n2)
        {
            //Console.WriteLine("From class 2, interface ???");
            this.str2 = this.str2.Substring(n2);
        }

        public void F0(int n, out string s)
        {
            s = this.str2;
            //Console.WriteLine("From class 2, interface Iy");
            s = s.Substring(n);
        }

    }
    class Program
    {
        static void Main(string[] args)
        {
            Cl1 x1 = new Cl1("abcdef");
            (x1 as Ix).F1(2);
            Console.WriteLine(x1.str1);
            Cl1 x12 = new Cl1("abcdef");
            (x12 as Iy).F1(2);
            Console.WriteLine(x12.str1);
            Console.ReadLine();
        }
    }
}