using System;

​

public interface IOperator<T, U> where T : IComparable<U>

{

    bool Compare(T a, U b);

}

​

public class EqualityOperator<T, U> : IOperator<T, U> where T : IComparable<U>

{

    public bool Compare(T a, U b) {

      return a.CompareTo(b) == 0;

    }

}

​

public class Filter<T, U> where T : IComparable<U> {

    public IOperator<T, U> storedOperator;

}

​

public class Program

{

    public static void Main()

    {

        EqualityOperator<int, int> test = new EqualityOperator<int, int>();

        test.Compare(1, 3);

    }

}