gistfile1.txt

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

namespace Day12
{
    class PlantGenerations
    {
        public string InitialState { get; }
        public Dictionary<string, char> Rules { get; }
        public int NumberOfGenerations { get; }
        public Dictionary<int, string> Generations;

        public PlantGenerations(string initialState, Dictionary<string, char> rules, int numberOfGens)
        {
            InitialState = initialState;
            Rules = rules;
            NumberOfGenerations = numberOfGens;
            Generations = new Dictionary<int, string>(NumberOfGenerations) {
                { 0, initialState }
            };
        }

        public void Run ()
        {
            Console.WriteLine("I've run");
            int genCount = 0;
            while (genCount < NumberOfGenerations)
            {
                var originalGen = $"..{Generations[genCount]}..";
                var nextGen = new StringBuilder (originalGen);

                for (int i = 2; i < originalGen.Length - 3; i++)
                {
                    var segment = originalGen.Substring(i - 2, 5);
                    if (Rules.ContainsKey(segment))
                        nextGen[i] = Rules[segment];
                    else
                        nextGen[i] = '.';
                }

                genCount++;
                Generations.Add(genCount, nextGen.ToString());
            }

            PrintGenerations();
            PrintPotCount();
        }

        public void PrintGenerations ()
        {
            foreach (var gen in Generations)
            {
                Console.WriteLine($"{gen.Key:00} -> {gen.Value}");
            }
        }

        public void PrintPotCount()
        {
            int count = 0;
            foreach (var genValues in Generations.Values)
            {
                count += genValues.Count(x => x == '#');
            }

            Console.WriteLine($"Pot count: {count}");
        }
    }
}