using System;

public class Program

{

    public class Test 

    {

        public int A { get; private set; }

        public int B { get; }

        public Test(int A, int B) {

            this.A = A;

            this.B = B;

        }

        public Test(Test original, int B) {

            A = original.A;

            this.B = B;

        }

        public Test Clone() {

            return (Test)this.MemberwiseClone();

        }

        public Test Clone(int A) {

            var clone = Clone();

            clone.A = A;

            return clone;

        }

        public override string ToString() {

            return $"{A} {B}";

        }

    }

    public static void Main()

    {

        var test = new Test(1,2);

        Console.WriteLine($"Original {test}\n");

        var overridePrivate = test.Clone(A: 66);

        Console.WriteLine($"Private prop overriden {overridePrivate}");

        Console.WriteLine($"Original did not change {test}\n");

        var overrideReadOnly = new Test(test, B: 66);

        Console.WriteLine($"ReadOnly prop overriden {overrideReadOnly}");

        Console.WriteLine($"Original did not change {test}\n");

    }

}