day 10 part 2 wip

AdventOfCode/Problems/AOC2025/Day10/Factory.cs

@@ -0,0 +1,139 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace AdventOfCode.Problems.AOC2025.Day10;
+
+[ProblemInfo(2025, 10, "Factory")]
+internal class Factory : Problem<int, int>
+{
+	private List<Machine> _data = [];
+
+	public override void CalculatePart1()
+	{
+		var results = new int[_data.Count];
+		Parallel.ForEach(_data, (m, _, i) => results[i] = m.SolveLights());
+		Part1 = results.Sum();
+	}
+
+	public override void CalculatePart2()
+	{
+		var results = new int[_data.Count];
+		Parallel.ForEach(_data, (m, _, i) => results[i] = m.SolveJoltage());
+		Part2 = results.Sum();
+	}
+
+	public override void LoadInput()
+	{
+		_data = ReadInputLines("input.txt").Select(l => new Machine(l)).ToList();
+	}
+
+	public class Machine
+	{
+		public bool[] Target { get; private set; }
+		public int[][] Operations { get; private set; }
+		public int[] Requirements { get; private set; }
+
+		public Machine(string data)
+		{
+			var sections = data.Split(' ');
+			Target = sections[0][1..^1].Select(c => c == '.' ? false : true).ToArray();
+			Operations = sections[1..^1].Select(op => op[1..^1])
+				.Select(op => op.Split(',').Select(int.Parse).ToArray())
+				.ToArray();
+			Requirements = sections[^1][1..^1].Split(',').Select(int.Parse).ToArray();
+		}
+
+		public int SolveLights()
+		{ 
+			var state = Enumerable.Repeat(false, Target.Length).ToArray();
+			var best = Target.Length;
+			return Solve(Target, Operations, state, ref best);
+
+			static int Solve(bool[] goal, int[][] operations, bool[] curState, ref int best, int depth = 0)
+			{
+				static bool IsSolved(bool[] goal, bool[] state)
+				{
+					for (int i = 0; i < goal.Length; i++)
+					{
+						if (goal[i] != state[i])
+							return false;
+					}
+					return true;
+				}
+
+				if (IsSolved(goal, curState))
+					return depth;
+				if (depth >= best)
+					return depth;
+
+				var opCount = int.MaxValue;
+				foreach (var op in operations)
+				{
+					var state = new bool[curState.Length];
+					Buffer.BlockCopy(curState, 0, state, 0, curState.Length);
+					
+					foreach (var idx in op)
+						state[idx] = !curState[idx];
+					var c = Solve(goal, operations, state, ref best, depth + 1);
+					if (c < best)
+						best = c;
+					if (c < opCount)
+						opCount = c;
+				}
+				return opCount;
+			}
+		}
+
+		public int SolveJoltage()
+		{
+			var state = new int[Requirements.Length];
+			var best = int.MaxValue;
+			return Solve(Requirements, Operations, state, ref best);
+			static int Solve(int[] target, int[][] operations, int[] curState, ref int best, int depth = 0)
+			{
+				if (depth > best)
+					return int.MaxValue;
+				if (IsOver(target, curState))
+					return int.MaxValue;
+				if (IsSolved(target, curState))
+				{
+					if (depth < best)
+						best = depth;
+					return depth;
+				}
+				static bool IsOver(int[] target, int[] curState) 
+				{
+					for (int i = 0; i < target.Length; i++)
+					{
+						if (target[i] < curState[i])
+							return true;
+					}
+					return false;
+				}
+				static bool IsSolved(int[] target, int[] curState)
+				{
+					for (int i = 0; i < target.Length; i++)
+					{
+						if (target[i] != curState[i])
+							return false;
+					}
+					return true;
+				}
+				var opCount = int.MaxValue;
+				foreach (var op in operations)
+				{
+					var state = new int[curState.Length];
+					Buffer.BlockCopy(curState, 0, state, 0, curState.Length * sizeof(int));
+					foreach (var idx in op)
+						state[idx] += 1;
+
+					var c = Solve(target, operations, state, ref best, depth + 1);
+					if (c < opCount)
+						opCount = c;
+				}
+				return opCount;
+			}
+		}
+	}
+}

AdventOfCode/Problems/AOC2025/Day4/PrintingDeparment.cs

@@ -1,6 +1,7 @@
 using AdventOfCode.Utils.Models;
 
 using System;
+using System.Collections.Frozen;
 using System.Collections.Generic;
 using System.Text;
 
@@ -13,36 +14,23 @@ internal class PrintingDeparment: Problem<int, int>
 
 	public override void CalculatePart1()
 	{
-		var c = 0;
+		Part1 = GetAccessableRolls(_data, _size).Count;
-		for (int y = 0; y < _size.Y; y++)
-		{
-			for (int x = 0; x < _size.X; x++)
-			{
-				var pos = new Vec2<int>(x, y);
-				if (_data[pos.Y][pos.X] != '@')
-					continue;
-				var n = CountNeighbors(pos);
-				if (n < 4)
-					c++;
-			}
-		}
-		Part1 = c;
 	}
 
-	public int CountNeighbors(Vec2<int> pos)
+	public static int CountNeighbors(string[] data, Vec2<int> size, Vec2<int> pos)
 	{
 		var c = 0;
 		for (int y = pos.Y-1; y <= pos.Y + 1; y++)
 		{
-			if (y < 0 || y >= _size.Y)
+			if (y < 0 || y >= size.Y)
 				continue;
 			for (int x = pos.X - 1; x <= pos.X + 1; x++)
 			{
-				if (x < 0 || x >= _size.X)
+				if (x < 0 || x >= size.X)
 					continue;
 				if (pos.X == x && pos.Y == y)
 					continue;
-				if (_data[y][x] == '@')
+				if (data[y][x] == '@')
 					c++;
 			}
 		}
@@ -51,7 +39,50 @@ internal class PrintingDeparment: Problem<int, int>
 
 	public override void CalculatePart2()
 	{
-		throw new NotImplementedException();
+		var data = _data;
+		var rolls = GetAccessableRolls(data, _size);
+		Part2 += rolls.Count;
+		while(rolls.Count > 0)
+		{
+			data = RemoveRolls(data, _size, rolls);
+			rolls = GetAccessableRolls(data, _size);
+			Part2 += rolls.Count;
+		}
+	}
+
+	public static List<Vec2<int>> GetAccessableRolls(string[] data, Vec2<int> size)
+	{
+		var results = new List<Vec2<int>>();
+		for (int y = 0; y < size.Y; y++)
+		{
+			for (int x = 0; x < size.X; x++)
+			{
+				var pos = new Vec2<int>(x, y);
+				if (data[pos.Y][pos.X] != '@')
+					continue;
+				var n = CountNeighbors(data, size, pos);
+				if (n < 4)
+					results.Add(pos);
+			}
+		}
+		return results;
+	}
+
+	public static string[] RemoveRolls(string[] data, Vec2<int> size, List<Vec2<int>> rolls)
+	{
+		var positions = rolls.ToFrozenSet();
+		return data.Select((row, y) =>
+		{
+			var updatedRow = row.Select((col, x) =>
+			{
+				var pos = new Vec2<int>(x, y);
+				if (positions.Contains(pos))
+					return '.';
+				else
+					return col;
+			}).ToArray();
+			return new string(updatedRow);
+		}).ToArray();
 	}
 
 	public override void LoadInput()

AdventOfCode/Problems/AOC2025/Day8/Playground.cs

@@ -9,49 +9,42 @@ namespace AdventOfCode.Problems.AOC2025.Day8;
 [ProblemInfo(2025, 8, "Playground")]
 internal class Playground : Problem<long, long>
 {
-	private Vec3<int>[] _boxPositions= [];
+	private Vec3i[] _boxPositions= [];
 
 	public override void CalculatePart1()
 	{
-		var boxes = _boxPositions.Select((p, i) => new JunctionBox(i, p, [])).ToArray();
+		var networks = new List<Network>();
 		var closest = GetClosestPairs(_boxPositions, 1000);
 		foreach (var (a, b)in closest)
 		{
-			var boxA = boxes.First(box => box.Pos == a);
+			var existingNetworkA = networks.FirstOrDefault(n => n.Members.Contains(a));
-			var boxB = boxes.First(box => box.Pos == b);
+			var existingNetworkB = networks.FirstOrDefault(n => n.Members.Contains(b));
-			boxA.Connections.Add(boxB.Id);
+			if ((existingNetworkA != null && existingNetworkB == null))
-			boxB.Connections.Add(boxA.Id);
+				existingNetworkA.AddConnection(a, b);
+			else if (existingNetworkB != null && existingNetworkA == null)
+				existingNetworkB.AddConnection(a, b);
+			else if (existingNetworkA != null && existingNetworkB != null && existingNetworkA != existingNetworkB)
+			{
+				existingNetworkA.AddConnection(a, b);
+				existingNetworkA.MergeWith(existingNetworkB);
+				networks.Remove(existingNetworkB);
+			}
+			else if(existingNetworkA == null && existingNetworkB == null)
+			{
+				var newNetwork = new Network().AddConnection(a, b);
+				networks.Add(newNetwork);
+			}
 		}
-		var networks = TraceNetworks(boxes);
+		Console.WriteLine($"Networks: {networks.Count}");
-		Part1 = networks.Select(n => (long)n.Count).OrderDescending().Take(3).Aggregate((a, b) => a * b);
+		Part1 = networks.Select(n => n.Members.Count)
+			.OrderDescending()
+			.Take(3)
+			.Aggregate((a, b) => a * b);
 	}
 
-	private static List<HashSet<int>> TraceNetworks(JunctionBox[] junctionBoxes)
+	private static List<(Vec3i a , Vec3i b)> GetClosestPairs(Vec3i[] boxes, int count = 10)
 	{
-		var networks = new List<HashSet<int>>();
+		var distances = new Dictionary<(Vec3i a, Vec3i b), double>();
-		foreach (var box in junctionBoxes)
-		{
-			if (networks.Any(n => n.Contains(box.Id)))
-				continue;
-			var net = new HashSet<int>() { box.Id };
-			TraceJunction(box, junctionBoxes, net);
-			networks.Add(net);
-		}
-		return networks;//.Where(n => n.Count > 0).ToList();
-	}
-
-	private static void TraceJunction(JunctionBox box, JunctionBox[] boxes, HashSet<int> result)
-	{
-		foreach (var connection in box.Connections)
-		{
-			if (result.Add(connection))
-				TraceJunction(boxes[connection], boxes, result);
-		}
-	}
-
-	private static List<(Vec3<int> a , Vec3<int> b)> GetClosestPairs(Vec3<int>[] boxes, int count = 10)
-	{
-		var distances = new Dictionary<(Vec3<int> a, Vec3<int> b), double>();
 
 		for (int i = 0; i < boxes.Length; i++)
 		{
@@ -74,11 +67,63 @@ internal class Playground : Problem<long, long>
 
 	public override void LoadInput()
 	{
-		_boxPositions = ReadInputLines("input.txt")
+		_boxPositions = ReadInputLines("sample.txt")
 			.Select(l => l.Split(',').Select(int.Parse))
-			.Select(c => new Vec3<int>(c.First(), c.Skip(1).First(), c.Last()))
+			.Select(c => new Vec3i(c.First(), c.Skip(1).First(), c.Last()))
 			.ToArray();
 	}
 
-	private record class JunctionBox(int Id, Vec3<int> Pos, HashSet<int> Connections);
+	private record class JunctionBox(Vec3i Pos, HashSet<Vec3i> Connections);
+
+	private class Network
+	{
+		public HashSet<Vec3i> Members { get; private set; } = [];
+		public List<JunctionBox> Boxes { get; private set; } = [];
+
+		public bool IsConnectedTo(Vec3i pos)
+		{
+			return Members.Contains(pos);
+		}
+
+		public bool IntersectsWith(Network other)
+		{
+			return Members.Intersect(other.Members).Any();
+		}
+
+		public Network AddConnection(Vec3i a, Vec3i b)
+		{
+			if (Members.Contains(a) && Members.Contains(b))
+				return this;
+			Members.Add(a);
+			Members.Add(b);
+			var boxA = GetOrAddBox(a);
+			var boxB = GetOrAddBox(b);
+			boxA.Connections.Add(b);
+			boxB.Connections.Add(a);
+			return this;
+		}
+
+		private JunctionBox GetOrAddBox(Vec3i pos)
+		{
+			var box = Boxes.FirstOrDefault(box => box.Pos == pos);
+			if(box == null)
+			{
+				box = new JunctionBox(pos, []);
+				Boxes.Add(box);
+			}
+			return box;
+		}
+
+		public Network MergeWith(Network other)
+		{
+			foreach (var box in other.Boxes)
+			{
+				foreach (var connection in box.Connections)
+				{
+					AddConnection(box.Pos, connection);
+				}
+			}
+			return this;
+		}
+	}
 }

AdventOfCode/Program.cs

@@ -4,4 +4,4 @@ global using AdventOfCode.Utils;
 
 
 var runner = new AOCRunner();
-runner.WithDay(8).RenderInteractiveMenu();
+runner.RenderInteractiveMenu();

AdventOfCode/Utils/Models/Common.cs

@@ -1,4 +1,10 @@
-using System.Numerics;
+global using Vec3i = AdventOfCode.Utils.Models.Vec3<int>;
+global using Vec2i = AdventOfCode.Utils.Models.Vec2<int>;
+global using Vec3l = AdventOfCode.Utils.Models.Vec3<long>;
+global using Vec2l = AdventOfCode.Utils.Models.Vec2<long>;
+global using Vec3f = AdventOfCode.Utils.Models.Vec3<float>;
+global using Vec2f = AdventOfCode.Utils.Models.Vec2<float>;
+using System.Numerics;
 
 namespace AdventOfCode.Utils.Models;
 
@@ -65,7 +71,7 @@ public record struct Vec3<T>(T X, T Y, T Z) where T : INumber<T>
 		var a = other.X - this.X;
 		var b = other.Y - this.Y;
 		var c = other.Z - this.Z;
-		return (a * a) + (b * b) + (c * c);
+		return T.Abs((a * a) + (b * b) + (c * c));
 	}
 
 	public readonly Vec3<T> Min(Vec3<T> other) => new(T.Min(X, other.X), T.Min(Y, other.Y), T.Min(Z, other.Z));