diff --git a/UCommon.pas b/UCommon.pas
index 0e674d9..bae26e7 100644
--- a/UCommon.pas
+++ b/UCommon.pas
@@ -22,7 +22,7 @@ unit UCommon;
 interface
 
 uses
-  Classes, SysUtils;
+  Classes, SysUtils, Generics.Collections;
 
 type
   PPoint = ^TPoint;
@@ -39,6 +39,10 @@ const
   CDirectionLeftUp: TPoint = (X: -1; Y: -1);
   CPCardinalDirections: array[0..3] of PPoint = (@CDirectionRight, @CDirectionDown, @CDirectionLeft, @CDirectionUp);
 
+type
+  TIntegerList = specialize TList<Integer>;
+  TPoints = specialize TList<TPoint>;
+
 implementation
 
 end.
diff --git a/solvers/UCosmicExpansion.pas b/solvers/UCosmicExpansion.pas
index 5f77003..7919ca6 100644
--- a/solvers/UCosmicExpansion.pas
+++ b/solvers/UCosmicExpansion.pas
@@ -22,7 +22,7 @@ unit UCosmicExpansion;
 interface
 
 uses
-  Classes, SysUtils, Generics.Collections, Math, USolver;
+  Classes, SysUtils, Generics.Collections, Math, USolver, UCommon;
 
 const
   CGalaxyChar = '#';
@@ -36,8 +36,8 @@ type
   TCosmicExpansion = class(TSolver)
   private
     FExpansionFactor: Integer;
-    FColumnExpansion, FRowExpansion: specialize TList<Integer>;
-    FGalaxies: specialize TList<TPoint>;
+    FColumnExpansion, FRowExpansion: TIntegerList;
+    FGalaxies: TPoints;
     procedure InitColumnExpansion(const ASize: Integer);
   public
     constructor Create(const AExpansionFactor: Integer = 999999);
@@ -67,9 +67,9 @@ end;
 constructor TCosmicExpansion.Create(const AExpansionFactor: Integer);
 begin
   FExpansionFactor := AExpansionFactor;
-  FColumnExpansion := specialize TList<Integer>.Create;
-  FRowExpansion := specialize TList<Integer>.Create;
-  FGalaxies := specialize TList<TPoint>.Create;
+  FColumnExpansion := TIntegerList.Create;
+  FRowExpansion := TIntegerList.Create;
+  FGalaxies := TPoints.Create;
 end;
 
 destructor TCosmicExpansion.Destroy;
diff --git a/solvers/ULongWalk.pas b/solvers/ULongWalk.pas
index 4af7fb5..e66e5ca 100644
--- a/solvers/ULongWalk.pas
+++ b/solvers/ULongWalk.pas
@@ -25,8 +25,6 @@ uses
   Classes, SysUtils, Generics.Collections, USolver, UCommon;
 
 type
-  TPoints = specialize TList<TPoint>;
-
   TCrossing = class;
 
   { TPath }
diff --git a/solvers/UStepCounter.pas b/solvers/UStepCounter.pas
index 6227d12..0a22c10 100644
--- a/solvers/UStepCounter.pas
+++ b/solvers/UStepCounter.pas
@@ -25,7 +25,6 @@ uses
   Classes, SysUtils, Generics.Collections, USolver, UCommon;
 
 type
-  TPoints = specialize TList<TPoint>;
 
   { TStepCounter }