diff --git a/AdvendOfCode.Runner/Program.cs b/AdvendOfCode.Runner/Program.cs
index dee3346..1289619 100644
--- a/AdvendOfCode.Runner/Program.cs
+++ b/AdvendOfCode.Runner/Program.cs
@@ -7,9 +7,9 @@ InputReader inputReader = new()
     //IsDebug = true
 };
 
-inputReader.SetInputByChallange(14);
+inputReader.SetInputByChallange(12);
 
-IChallange challange = new Day14(inputReader);
+IChallange challange = new Day12(inputReader);
 
 Console.WriteLine($"Part 1: {await challange.GetSolutionPart1()}");
 
diff --git a/AdventOfCode.Solutions/2023/Day 12/Day12.cs b/AdventOfCode.Solutions/2023/Day 12/Day12.cs
index ae9aa42..15624ca 100644
--- a/AdventOfCode.Solutions/2023/Day 12/Day12.cs	
+++ b/AdventOfCode.Solutions/2023/Day 12/Day12.cs	
@@ -1,4 +1,5 @@
 using AdventOfCode.Core;
+using System.Linq;
 using System.Text.RegularExpressions;
 
 namespace AdventOfCode.Solutions._2023
@@ -15,7 +16,11 @@ namespace AdventOfCode.Solutions._2023
                 string[] splitted = line.Split(' ');
                 int[] groups = splitted[1].Split(',').Select(int.Parse).ToArray();
 
-                total += Possibilities(splitted[0], groups);
+                Console.Write(splitted[0]);
+                long possiblies = Possibilities2(splitted[0], groups, 0, 0);
+                Console.WriteLine($": {possiblies}");
+                total += possiblies;
+                //total += Possibilities(splitted[0], groups);
             }
             return total.ToString();
         }
@@ -30,7 +35,11 @@ namespace AdventOfCode.Solutions._2023
                 int[] groups = splitted[1].Split(',').Select(int.Parse).ToArray();
                 int[] groupsTotal = groups.Concat(groups).Concat(groups).Concat(groups).Concat(groups).ToArray();
 
-                total += Possibilities2(joinedLine, groupsTotal, 0, 0, 0);
+                //total += Possibilities(splitted[0], groups);
+                Console.Write(joinedLine + " " + string.Join(",", new[] { splitted[1], splitted[1], splitted[1], splitted[1], splitted[1] }));
+                long possiblies = Possibilities2(joinedLine, groupsTotal, 0, 0);
+                Console.WriteLine($": {possiblies}");
+                total += possiblies;
             }
             return total.ToString();
         }
@@ -59,80 +68,92 @@ namespace AdventOfCode.Solutions._2023
                 return 0;
         }
 
-        private long Possibilities2(string lineToValidate, int[] groups, int readIndex, int groupIndex, int captureSize)
+        private long Possibilities2(string lineToValidate, int[] groups, int readIndex, int captureSize)
         {
-            // if group index is 0 there are no captures and not captures ruynning
-            if (groupIndex > 0)
+            // if group index is 0 there are no captures and not captures running
+            if (readIndex < lineToValidate.Length)
             {
-                int[] splitGroups = lineToValidate.Split('.', StringSplitOptions.RemoveEmptyEntries).Select(s => s.Length).ToArray();
+                int[] splitGroups = lineToValidate[..readIndex].Split('.', StringSplitOptions.RemoveEmptyEntries).Select(s => s.Length).ToArray();
 
-                // something to validate!
-                if (readIndex < lineToValidate.Length && // not reached the end
-                    lineToValidate[readIndex] == '.' && // possible end of capture
-                    captureSize > 0) // in capture mode but with a . caputure has ended
+                if (groups.Length < splitGroups.Length)
                 {
-                    for (int i = 0; i < groupIndex; i++)
-                    {
-                        if (splitGroups[i] != groups[i])
-                        {
-                            Console.WriteLine($"{lineToValidate} is invalid");
-                            return 0; // group lengths do not match, reject
-                        }
-                    }
-
-                    // valid so far
-                    // reset the capture size
-                    groupIndex++;
-                    captureSize = 0;
+                    // we have more groups than expected
+                    return 0;
                 }
 
-                
+                if (lineToValidate.Length - readIndex < groups.Skip(splitGroups.Length).Sum() + groups.Length - splitGroups.Length - 1)
+                {
+                    // there is not enough space to even fit the groups so reject
+                    return 0;
+                }
+
+                // validate everything, including fixed groups
+                for (int i = 0; i < splitGroups.Length - 1; i++)
+                {
+                    // all except the last must match
+                    if (splitGroups[i] != groups[i])
+                    {
+                        return 0; // group lengths do not match, reject
+                    }
+                }
+
+                // the last one is allowed to be smaller than the expected groups size
+                if (splitGroups.Any() && splitGroups[^1] > groups[splitGroups.Length - 1])
+                {
+                    // if the last group is larger than allowed the line is invalid
+                    return 0;
+                }
             }
 
             if (!lineToValidate.Contains('?')) // no more variations
             {
                 int[] splitGroups = lineToValidate.Split('.', StringSplitOptions.RemoveEmptyEntries).Select(s => s.Length).ToArray();
+                if (splitGroups.Length != groups.Length)
+                {
+                    // group amount does not match
+                    return 0;
+                }
+
                 for (int i = 0; i < groups.Length; i++)
                 {
                     if (splitGroups[i] != groups[i])
                     {
-                        Console.WriteLine($"{lineToValidate} is invalid");
                         return 0; // group lengths do not match, reject
                     }
                 }
 
-                // not invalid combos so valid
+                // valid combos so valid
                 return 1;
             }
 
-            //if (lineToValidate[readIndex] is '.' )
-
             long total = 0;
             //go search for # or ?
             for (int charIndex = readIndex; charIndex < lineToValidate.Length; charIndex++)
             {
                 if (lineToValidate[charIndex] == '.')
                 {
+                    captureSize = 0;
                     readIndex++;
                     continue;
                 }
 
                 if (lineToValidate[charIndex] == '#')
                 {
-                    total += Possibilities2(lineToValidate, groups, readIndex + 1, groupIndex + 1, captureSize + 1);
-                    break;
+                    captureSize++;
+                    readIndex++;
+                    continue;
                 }
 
                 if (lineToValidate[charIndex] == '?')
                 {
                     var regex = new Regex(Regex.Escape("?"));
-                    total += Possibilities2(regex.Replace(lineToValidate, ".", 1), groups, readIndex + 1, groupIndex, captureSize);
-                    total += Possibilities2(regex.Replace(lineToValidate, "#", 1), groups, readIndex + 1, groupIndex, captureSize + 1);
+                    total += Possibilities2(regex.Replace(lineToValidate, "#", 1), groups, readIndex + 1, captureSize + 1);
+                    total += Possibilities2(regex.Replace(lineToValidate, ".", 1), groups, readIndex + 1, captureSize);
                     return total;
                 }
             }
 
-            return 0;
+            return Possibilities2(lineToValidate, groups, readIndex + 1, captureSize);
         }
 
         [GeneratedRegex("#+")]
diff --git a/AdventOfCode.Solutions/day-00-input.txt b/AdventOfCode.Solutions/day-00-input.txt
index b92d1a3..c5bec3a 100644
--- a/AdventOfCode.Solutions/day-00-input.txt
+++ b/AdventOfCode.Solutions/day-00-input.txt
@@ -1,10 +1,6 @@
-O....#....
-O.OO#....#
-.....##...
-OO.#O....O
-.O.....O#.
-O.#..O.#.#
-..O..#O..O
-.......O..
-#....###..
-#OO..#....
\ No newline at end of file
+???.### 1,1,3
+.??..??...?##. 1,1,3
+?#?#?#?#?#?#?#? 1,3,1,6
+????.#...#... 4,1,1
+????.######..#####. 1,6,5
+?###???????? 3,2,1
\ No newline at end of file