using System;

using System.Globalization;

using System.Numerics;

​

public class Program

{

    public static void Main()

    {

​

        var chave1 = BigInteger.Parse("B6D6DF9DA7978062F7BCF768E5A8A84C", NumberStyles.AllowHexSpecifier);

        var chave2 = BigInteger.Parse("910DB02CF8FE34FBF1322073E6896E10", NumberStyles.AllowHexSpecifier);

        var exclusive = chave1 ^ chave2;

        var chave = exclusive.ToString("X");

​

​

        Console.WriteLine(chave);

    }

}