AorB Csharp ocde - study code

AorB_studyCsharp_Ex3.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace AOrB
{
    public static class Solution
    {
        public static string FromBinToHex(this string bininput)
        {
            StringBuilder output = new StringBuilder();
            for (int i = 0; i < bininput.Length; i += 4)
            {
                output.Append(Convert.ToInt32(bininput.Substring(i, 4), 2).ToString("X"));
            }
            return output.ToString();
        }
        public class Query
        {
            public string A { get; set; }
            public string B { get; set; }
            public string C { get; set; }

            public int K { get; set; }
            private void Calculate()
            {
                #region Padding
                int width = Math.Max(A.Length, Math.Max(B.Length, C.Length));
                A = A.PadLeft(width, '0');
                B = B.PadLeft(width, '0');
                C = C.PadLeft(width, '0');
                #endregion
                StringBuilder a_builder = new StringBuilder();
                StringBuilder b_builder = new StringBuilder();
                for (int i = 0; i < C.Length; i++)
                {
                    var aint = Convert.ToInt32(A[i].ToString(), 16);
                    var bint = Convert.ToInt32(B[i].ToString(), 16);
                    var cint = Convert.ToInt32(C[i].ToString(), 16);
                    if (aint == bint && bint == cint)
                    {
                        a_builder.Append(Convert.ToString(aint, 2).PadLeft(4, '0'));
                        b_builder.Append(Convert.ToString(aint, 2).PadLeft(4, '0'));
                        continue;
                    }
                    var a1 = Convert.ToString(aint, 2).PadLeft(4, '0').ToArray();
                    var b1 = Convert.ToString(bint, 2).PadLeft(4, '0').ToArray();
                    var c1 = Convert.ToString(cint, 2).PadLeft(4, '0').ToArray();

                    for (int ii = 0; ii < 4; ii++)
                    {
                        if (c1[ii] == '1')
                        {
                            if (a1[ii] == '0' && b1[ii] == '0')
                            {
                                b1[ii] = '1';
                                K--;

                            }

                        }
                        else
                        {
                            if (a1[ii] == '1')
                            {
                                a1[ii] = '0';
                                K--;
                            }
                            if (b1[ii] == '1')
                            {
                                b1[ii] = '0';
                                K--;
                            }
                        }
                    }
                    if (K < 0)
                        break;

                    a_builder.Append(string.Join("", a1));
                    b_builder.Append(string.Join("", b1));
                }

                if (K == 0)
                {
                    Ab = a_builder.ToString().FromBinToHex().TrimStart('0');
                    Bb = b_builder.ToString().FromBinToHex().TrimStart('0');
                }
                else if (K > 0)
                {
                    //Then we should be able to cancel out some one
                    var a_array = a_builder.ToString().ToArray();
                    var b_array = b_builder.ToString().ToArray();
                    for (var i = 0; i < a_array.Length; i++)
                    {
                        if (a_array[i] == '1') 
                        {
                            if (b_array[i] == '1')
                            {
                                a_array[i] = '0';
                                K--;
                            }
                            else if (K >= 2)
                            {
                                a_array[i] = '0';
                                b_array[i] = '1';
                                K -= 2;
                            }
                            if (K == 0)
                                break;
                        }
                        
                    }
                    Ab = string.Join("", a_array).FromBinToHex().TrimStart('0').PadLeft(1, '0');
                    Bb = string.Join("", b_array).FromBinToHex().TrimStart('0').PadLeft(1, '0');
                }

            }
            private string Ab;
            private string Bb;

            public void WriteResult(IConsole console)
            {
                Calculate();
                if (string.IsNullOrEmpty(Ab))
                    console.WriteLine("-1");
                else
                {
                    console.WriteLine(Ab.ToUpper());
                    console.WriteLine(Bb.ToUpper());
                }
            }
        }
        public static void Main(String[] args)
        {
            int queries = int.Parse(IOConsole.ReadLine());
            List<Query> qlist = new List<Query>();
            for (int i = 0; i < queries; i++)
            {
                qlist.Add(new Query
                {
                    K = int.Parse(IOConsole.ReadLine()),
                    A = IOConsole.ReadLine(),
                    B = IOConsole.ReadLine(),
                    C = IOConsole.ReadLine()
                });
            }
            foreach (var q in qlist)
                q.WriteResult(IOConsole);
        }

        public static IConsole IOConsole = new MyConsole();
    }

    public interface IConsole
    {
        string ReadLine();
        void WriteLine(string format, params object[] args);
    }
    public class MyConsole : IConsole
    {
        public string ReadLine()
        {
            return Console.ReadLine();
        }

        public void WriteLine(string format, params object[] args)
        {
            Console.WriteLine(format, args);
        }
    }
}