day 10

AdventOfCode/Problems/AOC2024/Day10/HoofIt.cs

@@ -1,25 +1,102 @@
-using System;
+using AdventOfCode.Utils.Models;
+
+using System;
 using System.Collections.Generic;
+using System.Drawing;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
 
 namespace AdventOfCode.Problems.AOC2024.Day10;
-//[ProblemInfo(2024, 10, "Hoof It")]
-internal class HoofIt : Problem
+[ProblemInfo(2024, 10, "Hoof It")]
+internal class HoofIt : Problem<int, int>
 {
+	private int[][] _data = [];
+
+	public static Vec2<int>[] DIRS = [
+			new(0, -1),
+			new(1, 0),
+			new(0, 1),
+			new(-1, 0),
+		];
+
 	public override void CalculatePart1()
 	{
-		throw new NotImplementedException();
+		for (int y = 0; y < _data.Length; y++)
+		{
+			var row = _data[y];
+			for (int x = 0; x < row.Length; x++)
+			{
+				var h = row[x];
+				if (h != 0)
+					continue;
+				var (s,_) = GetScore(new(x, y));
+				Part1 += s;
+			}
+		}
 	}
 
 	public override void CalculatePart2()
 	{
-		throw new NotImplementedException();
+		for (int y = 0; y < _data.Length; y++)
+		{
+			var row = _data[y];
+			for (int x = 0; x < row.Length; x++)
+			{
+				var h = row[x];
+				if (h != 0)
+					continue;
+				var (_, s) = GetScore(new(x, y));
+				Part2 += s;
+			}
+		}
+	}
+
+	public (int score, int scoreDistinct) GetScore(Vec2<int> pos)
+	{
+		return GetScore(pos, []);
+	}
+
+	public (int score, int scoreDistinct) GetScore(Vec2<int> pos, HashSet<Vec2<int>> visited)
+	{
+		var curHeight = _data[pos.Y][pos.X];
+		if (curHeight == 9)
+		{
+			if(visited.Contains(pos))
+				return (0, 1);
+			visited.Add(pos);
+			return (1, 1);
+		}
+
+		var score = 0;
+		var scoreDistinct = 0;
+		foreach (var dir in DIRS)
+		{
+			var n = pos + dir;
+			if (!IsInBounds(n))
+				continue;
+			var h = _data[n.Y][n.X];
+			if (h - curHeight != 1)
+				continue;
+			var (s, d)= GetScore(n, visited);
+			score += s;
+			scoreDistinct += d;
+		}
+
+		return (score, scoreDistinct);
+	}
+
+	public bool IsInBounds(Vec2<int> pos)
+	{
+		if (pos.X < 0 || pos.Y < 0) 
+			return false;
+		if(pos.X >= _data.Length || pos.Y >= _data[0].Length) 
+			return false;
+		return true;
 	}
 
 	public override void LoadInput()
 	{
-		throw new NotImplementedException();
+		_data = ReadInputLines("input.txt").Select(l => l.Select(v => v - '0').ToArray()).ToArray();
 	}
 }