Added day 9

Advend Of Code Runner/Program.cs

@@ -3,15 +3,18 @@
 using AdventOfCodeLibrary._2022;
 using AdventOfCodeLibrary.Shared;
 
-string _demoData = @"30373
-25512
-65332
-33549
-35390";
+string _demoData = @"R 4
+U 4
+L 3
+D 1
+R 4
+D 1
+L 5
+R 2";
 
-Answerable answerable = new Day08Part1();
+Answerable answerable = new Day09Part1();
 byte[] dataArray = File.ReadAllBytes(answerable.DefaultInputFile);
-//dataArray = Encoding.UTF8.GetBytes(_demoData);
+dataArray = Encoding.UTF8.GetBytes(_demoData);
 
 Console.WriteLine($"Max value: {answerable.GetAnswer(dataArray)}");
 Console.ReadKey(true); 

Advent Of Code Library/2022/Day 09/Day09Part1.cs

@@ -0,0 +1,20 @@
+namespace AdventOfCodeLibrary._2022
+{
+    using AdventOfCodeLibrary._2022.Day_09;
+    using AdventOfCodeLibrary.Shared;
+
+    public class Day09Part1 : Answerable
+    {
+        public override int Year { get; set; } = 2022;
+        public override int Day { get; set; } = 9;
+        public override int Part { get; set; } = 1;
+
+        public override string GetAnswer(byte[] data)
+        {
+            string[] movements = GetAsStringArray(data);
+            RopeWalker walker = new();
+
+            return walker.ProcessMovement(movements).ToString();
+        }
+    }
+}

Advent Of Code Library/2022/Day 09/Day09Part2.cs

@@ -0,0 +1,23 @@
+namespace AdventOfCodeLibrary._2022
+{
+    using AdventOfCodeLibrary.Shared;
+
+    public class Day09Part2 : Answerable
+    {
+        public override int Year { get; set; } = 2022;
+        public override int Day { get; set; } = 9;
+        public override int Part { get; set; } = 2;
+
+        public override string GetAnswer(byte[] data)
+        {
+            int markerLength = 14;
+            for (int skip = 0; skip < data.Length - 1 - markerLength; skip++)
+            {
+                if (data.Skip(skip).Take(markerLength).Distinct().Count() == markerLength)
+                    return (skip + markerLength).ToString();
+            }
+
+            return "nothing found";
+        }
+    }
+}

Advent Of Code Library/2022/Day 09/RopeWalker.cs

@@ -0,0 +1,94 @@
+namespace AdventOfCodeLibrary._2022.Day_09
+{
+    internal class VirtualPoint
+    {
+        internal int X { get; private set; } = 0;
+
+        internal int Y { get; private set; } = 0;
+
+        internal void MoveUp()
+        {
+            Y++;
+        }
+
+        internal void MoveDown()
+        {
+            Y--;
+        }
+
+        internal void MoveRight()
+        {
+            X++;
+        }
+
+        internal void MoveLeft()
+        {
+            X--;
+        }
+    }
+
+    internal class RopeWalker
+    {
+        private VirtualPoint HeadLocation = new();
+        private VirtualPoint LastHeadLocation = new();
+
+        private VirtualPoint TailLocation = new();
+
+        private List<string> TailVistedLocations = new();
+
+        internal int ProcessMovement(string[] movements)
+        {
+            // add the start position
+            TailVistedLocations.Add($"0,0");
+
+            for (int movementIndex = 0; movementIndex < movements.Length; movementIndex++)
+            {
+                char direction = movements[movementIndex][0];
+                int amountToMove = Convert.ToInt32(movements[movementIndex].Substring(2));
+
+                for (int movement = 0; movement < amountToMove; movement++)
+                {
+                    // set the last pos before moving
+                    LastHeadLocation = HeadLocation;
+
+                    // do the actual move
+                    switch (direction)
+                    {
+                        case 'U': HeadLocation.MoveUp(); break;
+                        case 'D': HeadLocation.MoveDown(); break;
+                        case 'R': HeadLocation.MoveRight(); break;
+                        case 'L': HeadLocation.MoveLeft(); break;
+                    }
+
+                    // check if the tail is touching
+                    if (!IsTailTouchingHead(direction))
+                    {
+                        // if not, move tail to last head position
+                        TailLocation = LastHeadLocation;
+
+                        // add the new position to the list of visited positions
+                        TailVistedLocations.Add($"{TailLocation.X},{TailLocation.Y}");
+                    }
+                }
+            }
+
+            return TailVistedLocations.Distinct().Count();
+        }
+
+        private bool IsTailTouchingHead(char direction)
+        {
+            return direction switch
+            {
+                // up; Y + 1
+                'U' => TailLocation.Y + 1 >= HeadLocation.Y,
+                // down; Y - 1
+                'D' => TailLocation.Y - 1 <= HeadLocation.Y,
+                // right; X + 1
+                'R' => TailLocation.X + 1 >= HeadLocation.X,
+                // left; X - 1
+                'L' => TailLocation.X - 1 <= HeadLocation.X,
+                _ => throw new AccessViolationException(),
+            };
+        }
+    }
+}