AdventOfCode/AdventOfCode.Solutions/2024/Day 01/Day01.cs

using AdventOfCode.Core.Shared.IO;

namespace AdventOfCode.Solutions._2024
{
    public class Day01 : IChallange
    {
        public int Year => 2024;
        public int Day => 1;

        private readonly IInputReader _inputReader;

        public Day01(IInputReader inputReader)
        {
            _inputReader = inputReader;
            _inputReader.SetInput(this);
        }

        //11
        //1889772
        public async Task<string> GetSolutionPart1()
        {
            int total = 0;
            (List<int> One, List<int> Two) = await GetLists();

            One = [.. One.Order()];
            Two = [.. Two.Order()];

            for (int index = 0; index < One.Count; index++) {
                int distance = Math.Abs(One[index] - Two[index]);
                total += distance;
            }

            return total.ToString();
        }

        //31
        //23228917
        public async Task<string> GetSolutionPart2()
        {
            int total = 0;
            (List<int> One, List<int> Two) = await GetLists();

            var oneGroup = One.GroupBy(x => x);
            var twoGroup = Two.GroupBy(x => x);
            
            foreach(var group in  oneGroup)
            {
                var grouptwo = twoGroup.FirstOrDefault(g => g.Key == group.Key)?.Count() ?? 0;
                total += group.Key * group.Count() * grouptwo;
            }

            return total.ToString();
        }

        private async Task<(List<int> One, List<int> Two)> GetLists()
        {
            string[] data = await _inputReader.ReadAsArrayString();
            List<int> one = [], two = [];
            foreach (string s in data)
            {
                int[] numbers = s.Split("  ").Select(int.Parse).ToArray();
                one.Add(numbers[0]);
                two.Add(numbers[1]);
            }

            return (one, two);
        }
    }
}