Day 7

AdventOfCode/AdventOfCode.csproj

@@ -52,6 +52,9 @@
 	<None Remove="problems\aoc2023\day5\sample.txt" />
 	<None Remove="problems\aoc2023\day6\input.txt" />
 	<None Remove="problems\aoc2023\day6\sample.txt" />
+	<None Remove="problems\aoc2023\day7\input.txt" />
+	<None Remove="problems\aoc2023\day7\sample.txt" />
+	<None Remove="problems\aoc2023\day7\sara.txt" />
   </ItemGroup>
 
 

AdventOfCode/Problems/AOC2023/Day7/CamelCards.cs

@@ -0,0 +1,36 @@
+using AdventOfCode.Runner.Attributes;
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace AdventOfCode.Problems.AOC2023.Day7;
+[ProblemInfo(2023, 7, "Camel Cards")]
+internal class CamelCards : Problem<int, int>
+{
+	private CamelHand[] _hands = [];
+	private CamelHand[] _jokerHands = [];
+
+	public override void LoadInput()
+	{
+		var data = ReadInputLines("input.txt");
+		_hands = data.Select(d => new CamelHand(d)).ToArray();
+		_jokerHands = data.Select(d => new CamelHand(d, true)).ToArray();
+	}
+
+	public override void CalculatePart1()
+	{
+		var x = _hands.Order();
+		Part1 = x.Select((h, i) => (i + 1) * h.Bid).Sum();
+	}
+
+	public override void CalculatePart2()
+	{
+		var x = _jokerHands.Order().Print();
+		//x.Where(x => x.Hand.Contains('J')).Print();
+		Part2 = x.Select((h, i) => (i + 1) * h.Bid).Sum();
+	}
+
+}

AdventOfCode/Problems/AOC2023/Day7/CamelHand.cs

@@ -0,0 +1,106 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace AdventOfCode.Problems.AOC2023.Day7;
+internal class CamelHand : IComparable<CamelHand>
+{
+	public static readonly List<char> CARDS = [ '2', '3', '4', '5', '6', '7', '8', '9', 'T', 'J', 'Q', 'K', 'A' ];
+	public static readonly List<char> CARDS_JOKER = [ 'J', '2', '3', '4', '5', '6', '7', '8', '9', 'T', 'Q', 'K', 'A' ];
+
+	public string Hand { get; set; }
+	public int Bid { get; set; }
+	public int Value { get; set; }
+	public HandType Type { get; set; }
+	public CamelHand(string data, bool useJoker = false)
+	{
+		var split = data.Split(' ');
+		Hand = split[0];
+		Bid = int.Parse(split[1]);
+		Type = useJoker ? GetJokerHandType(Hand) : GetHandType(Hand);
+		Value = CalculateValue(Hand, useJoker);
+	}
+
+	public static int CalculateValue(string hand, bool useJoker)
+	{
+		var total = 0;
+		for (int i = 0; i < hand.Length; i++)
+		{
+			var p = (hand.Length - i - 1);
+			var v = useJoker ? CARDS_JOKER.IndexOf(hand[i]) : CARDS.IndexOf(hand[i]);
+			total += (v + 1) * (int)Math.Pow(13, p);
+		}
+		return total;
+	}
+
+	public bool IsStrongerThan(CamelHand card)
+	{
+		if (Type > card.Type)
+			return true;
+		if(Type < card.Type) 
+			return false;
+
+		return Value >= card.Value;
+	}
+
+	private static HandType GetJokerHandType(string hand)
+	{
+		var type = GetHandType(hand);
+		if (type == HandType.FiveOfKind)
+			return type;
+
+		if (!hand.Contains('J'))
+			return type;
+		var bestCard = hand.GroupBy(c => c)
+			.OrderByDescending(c => c.Count())
+			.First(c => c.Key != 'J').Key;
+
+		var newHand = hand.Replace('J', bestCard);
+		return GetHandType(newHand);
+	} 
+	private static HandType GetHandType(string hand)
+	{
+		var cardGroups = hand.GroupBy(c => c).Select(g => g.Count()).ToArray();
+
+		if (cardGroups.Length == 1)
+			return HandType.FiveOfKind;
+		if(cardGroups.Contains(4))
+			return HandType.FourOfKind;
+		if (cardGroups.Contains(3) && cardGroups.Contains(2))
+			return HandType.FullHouse;
+		if(cardGroups.Contains(3))
+			return HandType.ThreeOfKind;
+
+		var pairs = cardGroups.Count(c => c == 2);
+		if (pairs == 2)
+			return HandType.TwoPair;
+		if (pairs == 1)
+			return HandType.OnePair;
+
+		return HandType.HighCard;
+	}
+
+	public int CompareTo(CamelHand? other)
+	{
+		if(other == null) return 1;
+		return IsStrongerThan(other) ? 1 : -1;
+	}
+
+	public override string ToString()
+	{
+		return $"[{Value}] {Hand}: {Type} | {Bid}";
+	}
+
+	public enum HandType
+	{
+		HighCard,
+		OnePair,
+		TwoPair,
+		ThreeOfKind,
+		FullHouse,
+		FourOfKind,
+		FiveOfKind
+	}
+}

AdventOfCode/Problems/AOC2023/Day7/sample.txt

@@ -0,0 +1,5 @@
+32T3K 765
+T55J5 684
+KTJJT 220
+KK677 28
+QQQJA 483

AdventOfCode/Runner/Extensions.cs

@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace AdventOfCode.Runner;
+public static class Extensions
+{
+	public static IEnumerable<T> Print<T>(this IEnumerable<T> values)
+	{
+		foreach (var item in values) 
+		{ 
+			Console.WriteLine(item);
+		}
+		return values;
+	}
+}