AdventOfCode23/Day18/Instruction.cs

using System.Drawing;

namespace Day18;

public record Instruction(char Dir, int Num, byte[] Scramble)
{
    private static readonly IDictionary<int, char> DirMap = new Dictionary<int, char>
    {
        [0] = 'R',
        [1] = 'D',
        [2] = 'L',
        [3] = 'U'
    };
    
    public Instruction Unscramble()
    {
        
        var code = BitConverter.ToInt32(Scramble.Reverse().Append((byte)0).ToArray());
        var dirIndex = code & 15; 
        var num = code >> 4;

        return new Instruction(DirMap[dirIndex], num, new byte[] { });
    }
}