From 9f1a2d2300e0220a0e3f546e1f2da4621b643a6b Mon Sep 17 00:00:00 2001
From: Amatsugu <khamraj@kaisei.app>
Date: Thu, 4 Dec 2025 12:58:34 -0500
Subject: [PATCH] day 4 pt 1

---
 .../AOC2025/Day4/PrintingDeparment.cs         | 62 +++++++++++++++++++
 AdventOfCode/Program.cs                       |  2 +-
 AdventOfCode/Utils/Models/Common.cs           | 10 +++
 3 files changed, 73 insertions(+), 1 deletion(-)
 create mode 100644 AdventOfCode/Problems/AOC2025/Day4/PrintingDeparment.cs

diff --git a/AdventOfCode/Problems/AOC2025/Day4/PrintingDeparment.cs b/AdventOfCode/Problems/AOC2025/Day4/PrintingDeparment.cs
new file mode 100644
index 0000000..18a56de
--- /dev/null
+++ b/AdventOfCode/Problems/AOC2025/Day4/PrintingDeparment.cs
@@ -0,0 +1,62 @@
+using AdventOfCode.Utils.Models;
+
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace AdventOfCode.Problems.AOC2025.Day4;
+[ProblemInfo(2025, 4, "Printing Department")]
+internal class PrintingDeparment: Problem<int, int>
+{
+	private string[] _data = [];
+	private Vec2<int> _size;
+
+	public override void CalculatePart1()
+	{
+		var c = 0;
+		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)
+	{
+		var c = 0;
+		for (int y = pos.Y-1; y <= pos.Y + 1; 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)
+					continue;
+				if (pos.X == x && pos.Y == y)
+					continue;
+				if (_data[y][x] == '@')
+					c++;
+			}
+		}
+		return c;
+	}
+
+	public override void CalculatePart2()
+	{
+		throw new NotImplementedException();
+	}
+
+	public override void LoadInput()
+	{
+		_data = ReadInputLines("input.txt");
+		_size = new Vec2<int>(_data[0].Length, _data.Length);
+	}
+}
diff --git a/AdventOfCode/Program.cs b/AdventOfCode/Program.cs
index b6b2c75..248aa77 100644
--- a/AdventOfCode/Program.cs
+++ b/AdventOfCode/Program.cs
@@ -4,4 +4,4 @@ global using AdventOfCode.Utils;
 
 
 var runner = new AOCRunner();
-runner.WithDay(2).RenderInteractiveMenu();
+runner.RenderInteractiveMenu();
diff --git a/AdventOfCode/Utils/Models/Common.cs b/AdventOfCode/Utils/Models/Common.cs
index 3107a08..748b78c 100644
--- a/AdventOfCode/Utils/Models/Common.cs
+++ b/AdventOfCode/Utils/Models/Common.cs
@@ -24,6 +24,11 @@ public record struct Vec2<T>(T X, T Y) where T : INumber<T>
 		var b = other.Y - this.Y;
 		return (a * a) + (b * b);
 	}
+
+	public override string ToString()
+	{
+		return $"({X}, {Y})";
+	}
 }
 
 public record struct Vec3<T>(T X, T Y, T Z) where T : INumber<T>
@@ -45,4 +50,9 @@ public record struct Vec3<T>(T X, T Y, T Z) where T : INumber<T>
 		var c = other.Z - this.Z;
 		return (a * a) + (b * b) + (c * c);
 	}
+
+	public override string ToString()
+	{
+		return $"({X}, {Y}, {Z})";
+	}
 }
\ No newline at end of file