feat: solved day 11 part 1 and part 2

11/PlutonianPebbles/Stone.cs

@@ -0,0 +1,41 @@
+namespace PlutonianPebbles;
+
+record Stone
+{
+  private readonly string _engravedValue;
+
+  private Stone(string engravedValue)
+  {
+    _engravedValue = engravedValue;
+  }
+
+  public static Stone From(string engraving) => new(engraving);
+
+  public List<Stone> Transform()
+  {
+    if (_engravedValue is "0")
+    {
+      return [new Stone("1")];
+    }
+
+    var hasOddNumberOfDigits = _engravedValue.Length % 2 is not 0;
+
+    if (hasOddNumberOfDigits)
+    {
+      var engravedNumber = long.Parse(_engravedValue);
+      var newEngravedValue = engravedNumber * 2024;
+      return [new(newEngravedValue.ToString())];
+    }
+
+    var middleIndex = _engravedValue.Length / 2;
+    var leftDigits = long.Parse(_engravedValue[..middleIndex]);
+    var rightDigits = long.Parse(_engravedValue[middleIndex..]);
+    
+    return [new(leftDigits.ToString()), new(rightDigits.ToString())];
+  }
+
+  public override string ToString()
+  {
+    return _engravedValue;
+  }
+}