AdventOfCode/Days/Day25.cs

using System.Collections.Frozen;
using System.Numerics;
using System.Runtime.CompilerServices;
using System.Runtime.Intrinsics.X86;
using System.Text;
using Microsoft.CodeAnalysis;
using Microsoft.VisualBasic;
using Spectre.Console;

namespace AdventOfCode.Days;

public class Day25 : Day
{
    public override int Number => 25;
    public override string Name => "Code Chronicle";

    public override void RunPart1(bool display = true)
    {
        var (locks, keys) = ParseInput();

        var workingPairs = 0;

        foreach (var lockToTest in locks)
        {
            foreach (var key in keys)
            {
                if (lockToTest.Height1 + key.Height1 < 6 &&
                    lockToTest.Height2 + key.Height2 < 6 &&
                    lockToTest.Height3 + key.Height3 < 6 &&
                    lockToTest.Height4 + key.Height4 < 6 &&
                    lockToTest.Height5 + key.Height5 < 6)
                {
                    workingPairs++;
                }
            }
        }

        if (display)
        {
            AnsiConsole.MarkupLine($"[green]Amont of unique key/lock pairs that fit: [yellow]{workingPairs}[/][/]");
        }
    }

    public override void RunPart2(bool display = true)
    {

    }

    private (List<Lock> Locks, List<Key> Keys) ParseInput()
    {
        var locks = new List<Lock>();
        var keys = new List<Key>();

        Span<int> itemHeights = stackalloc int[5];

        var input = Input.AsSpan();
        foreach (var itemRange in input.Split($"{Environment.NewLine}{Environment.NewLine}"))
        {
            var item = input[itemRange];
            var lines = item.EnumerateLines();

            var isKey = false;

            // Reset item heights
            itemHeights[0] = -1;
            itemHeights[1] = -1;
            itemHeights[2] = -1;
            itemHeights[3] = -1;
            itemHeights[4] = -1;

            for (var height = 0; height <= 6; height++)
            {
                lines.MoveNext();
                var line = lines.Current;

                if (height is 0)
                {
                    isKey = line is ".....";

                    continue;
                }

                for (var i = 0; i < 5; i++)
                {
                    if (isKey && line[i] is '#' && itemHeights[i] is -1)
                    {
                        itemHeights[i] = 6 - height;
                    }
                    else if (!isKey && line[i] is '.' && itemHeights[i] is -1)
                    {
                        itemHeights[i] = height - 1;
                    }
                }
            }

            if (isKey)
            {
                keys.Add(new Key(itemHeights[0], itemHeights[1], itemHeights[2], itemHeights[3], itemHeights[4]));
            }
            else
            {
                locks.Add(new Lock(itemHeights[0], itemHeights[1], itemHeights[2], itemHeights[3], itemHeights[4]));
            }
        }

        return (locks, keys);
    }

    private readonly record struct Lock(int Height1, int Height2, int Height3, int Height4, int Height5);
    private readonly record struct Key(int Height1, int Height2, int Height3, int Height4, int Height5);
}