September Morn Update

Task/Sorting-algorithms-Quicksort/Ada/sorting-algorithms-quicksort-1.ada

@@ -1,10 +1,9 @@
 -----------------------------------------------------------------------
--- Generic Quicksort procedure
+-- Generic Quick_Sort procedure
 -----------------------------------------------------------------------
 generic
-    type Element_Type is private;
-   type Index_Type is (<>);
-   type Element_Array is array(Index_Type range <>) of Element_Type;
-   with function "<" (Left, Right : Element_Type) return Boolean is <>;
-   with function ">" (Left, Right : Element_Type) return Boolean is <>;
-procedure Sort(Item : in out Element_Array);
+   type Element is private;
+   type Index is (<>);
+   type Element_Array is array(Index range <>) of Element;
+   with function "<" (Left, Right : Element) return Boolean is <>;
+procedure Quick_Sort(A : in out Element_Array);

Task/Sorting-algorithms-Quicksort/Ada/sorting-algorithms-quicksort-2.ada

@@ -1,50 +1,44 @@
 -----------------------------------------------------------------------
--- Generic Quicksort procedure
+-- Generic Quick_Sort procedure
 -----------------------------------------------------------------------
 
-procedure Sort (Item : in out Element_Array) is
+procedure Quick_Sort (A : in out Element_Array) is
 
-   procedure Swap(Left, Right : in out Element_Type) is
-      Temp : Element_Type := Left;
+   procedure Swap(Left, Right : Index) is
+      Temp : Element := A (Left);
    begin
-      Left := Right;
-      Right := Temp;
+      A (Left) := A (Right);
+      A (Right) := Temp;
    end Swap;
 
-   Pivot_Index : Index_Type;
-   Pivot_Value : Element_Type;
-   Right       : Index_Type := Item'Last;
-   Left        : Index_Type := Item'First;
-
 begin
-   if Item'Length > 1 then
-      Pivot_Index := Index_Type'Val((Index_Type'Pos(Item'Last) + 1 +
-                                    Index_Type'Pos(Item'First)) / 2);
-      Pivot_Value := Item(Pivot_Index);
-
-      Left  := Item'First;
-      Right := Item'Last;
-      loop
-         while Left < Item'Last and then Item(Left) < Pivot_Value loop
-            Left := Index_Type'Succ(Left);
-         end loop;
-         while Right > Item'First and then Item(Right) > Pivot_Value loop
-            Right := Index_Type'Pred(Right);
-         end loop;
-         exit when Left >= Right;
-         Swap(Item(Left), Item(Right));
-         if Left < Item'Last then
-            Left := Index_Type'Succ(Left);
-         end if;
-         if Right > Item'First then
-            Right := Index_Type'Pred(Right);
-         end if;
-      end loop;
-      if Right > Item'First then
-         Sort(Item(Item'First..Index_Type'Pred(Right)));
-      end if;
-      if Left < Item'Last then
-         Sort(Item(Left..Item'Last));
-      end if;
+   if A'Length > 1 then
+   declare
+      Pivot_Value : Element := A (A'First);
+      Right       : Index := A'Last;
+      Left        : Index := A'First;
+   begin
+       loop
+          while Left < Right and not (Pivot_Value < A (Left)) loop
+             Left := Index'Succ (Left);
+          end loop;
+          while Pivot_Value < A (Right) loop
+             Right := Index'Pred (Right);
+          end loop;
+          exit when Right <= Left;
+          Swap (Left, Right);
+          Left := Index'Succ (Left);
+          Right := Index'Pred (Right);
+       end loop;
+       if Right = A'Last then
+          Right := Index'Pred (Right);
+          Swap (A'First, A'Last);
+       end if;
+       if Left = A'First then
+          Left := Index'Succ (Left);
+       end if;
+       Quick_Sort (A (A'First .. Right));
+       Quick_Sort (A (Left .. A'Last));
+   end;
    end if;
-end Sort;
+end Quick_Sort;

Task/Sorting-algorithms-Quicksort/Ada/sorting-algorithms-quicksort-3.ada

@@ -1,13 +1,12 @@
-with Sort;
 with Ada.Text_Io;
 with Ada.Float_Text_IO; use Ada.Float_Text_IO;
 
 procedure Sort_Test is
    type Days is (Mon, Tue, Wed, Thu, Fri, Sat, Sun);
-   type Sales is array(Days range <>) of Float;
-   procedure Sort_Days is new Sort(Float, Days, Sales);
+   type Sales is array (Days range <>) of Float;
+   procedure Sort_Days is new Quick_Sort(Float, Days, Sales);
 
-   procedure Print(Item : Sales) is
+   procedure Print (Item : Sales) is
    begin
       for I in Item'range loop
          Put(Item => Item(I), Fore => 5, Aft => 2, Exp => 0);