Merge pull request #187 from rpottsoh/updateBookStore

book-store: Update to v1.1.0

Author: rpottsoh

exercises/book-store/uBookStoreExample.pas

@@ -11,7 +11,7 @@ interface
 function NewBasket(aBasket: TArray<Integer>): IBasket;
 
 implementation
-uses System.SysUtils;
+uses System.SysUtils, System.Generics.collections, System.Math;
 
 const
   seriesBooks = '12345';
@@ -27,6 +27,7 @@   TBasket = class(TInterfacedObject, IBasket)
   private
     fSingleBookPrice: extended;
     fBasket: string;
+    fIntList: TList<integer>;
     class function Head(inStr: string): string; static;
     class function Tail(inStr: string): string; static;
     class function ConvertIntArrayToString(const aIntArray: TArray<Integer>): string; static;
@@ -65,6 +66,9 @@ class function TBasket.ConvertIntArrayToString(const aIntArray: TArray<Integer>)
 constructor TBasket.Create(aBasket: TArray<Integer>);
 begin
   fSingleBookPrice := 8;
+  fIntList := TList<integer>.Create;
+  fIntList.AddRange(aBasket);
+  fIntList.Sort;
   fBasket := ConvertIntArrayToString(aBasket);
 end;
 
@@ -108,26 +112,42 @@ function TBasket.GroupBasket:TArray<String>;
 end;
 
 function TBasket.Total:extended;
-var hpBook      : char;
-    totalBooks  : integer;
-    subBaskets  : TArray<String>;
-    wrkSubBasket: string;
-    subTotal    : extended;
+var
+    subBaskets    : TArray<String>;
+    subResult     : array[0..1] of extended;
+    lSortedBasket : TArray<integer>;
+
+    function computeTotal: extended;
+    var wrkSubBasket: string;
+        totalBooks  : integer;
+        subTotal    : extended;
+    begin
+      result := 0;
+      for wrkSubBasket in subBaskets do
+      begin
+        totalBooks := wrkSubBasket.Length;
+        subTotal := totalBooks * (fSingleBookPrice * DiscountPercentage(wrkSubBasket));
+        Result := Result + subTotal;
+      end;
+    end;
+
 begin
+  fillchar(subResult, sizeof(extended), #0);
+
   subBaskets := GroupBasket;
-  result := 0;
-  for wrkSubBasket in subBaskets do
-  begin
-    totalBooks := wrkSubBasket.Length;
-    subTotal := totalBooks * (fSingleBookPrice * DiscountPercentage(wrkSubBasket));
-    result := result + subTotal;
-  end;
+  subResult[0] := computeTotal;
+
+  lSortedBasket := fIntList.ToArray;
+  fBasket := ConvertIntArrayToString(lSortedBasket);
+  subBaskets := GroupBasket;
+  subResult[1] := computeTotal;
+
+  result := min(subResult[0], subResult[1]);
 end;
 
 function TBasket.DiscountPercentage(inStr : string):extended;
 var numDiffBooks: integer;
 begin
-  result := 1;
   numDiffBooks := NumberOfDifferentBooks(inStr);
   result := CDiscounts[numDiffBooks];
 end;

exercises/book-store/uBookStoreTests.pas

@@ -4,12 +4,15 @@ interface
 uses
   DUnitX.TestFramework;
 
+const
+   CanonicalVersion = '1.1.0';
+
 type
   [TestFixture]
   hpTests = class(TObject)
   public
     [Test]
-//  [Ignore('Comment the "[Ignore]" statement to run the test')]
+//    [Ignore('Comment the "[Ignore]" statement to run the test')]
     procedure A_basket_containing_only_a_single_book;
 
     [Test]
@@ -55,6 +58,10 @@   hpTests = class(TObject)
     [Test]
     [Ignore]
     procedure A_basket_containing_twelve_books_consisting_of_three_copies_of_the_first_two_books_plus_two_each_of_the_remaining_three_books_in_the_series;
+
+    [Test]
+    [Ignore]
+    procedure Four_groups_of_four_are_cheaper_than_two_groups_each_of_five_and_three;
   end;
 
 implementation
@@ -130,6 +137,34 @@ procedure hpTests.A_basket_with_three_different_books;
   assert.AreEqual(Expected, fBasket.Total, MinDelta, format('Total should be %0.2f',[Expected]));
 end;
 
+procedure hpTests.Four_groups_of_four_are_cheaper_than_two_groups_each_of_five_and_three;
+var Basket: TArray<integer>;
+    fBasket: IBasket;
+    Expected: double;
+begin
+  SetLength(Basket, 16);
+  Basket[0] := 1;
+  Basket[1] := 1;
+  Basket[2] := 2;
+  Basket[3] := 2;
+  Basket[4] := 3;
+  Basket[5] := 3;
+  Basket[6] := 4;
+  Basket[7] := 5;
+  Basket[8] := 1;
+  Basket[9] := 1;
+  Basket[10] := 2;
+  Basket[11] := 2;
+  Basket[12] := 3;
+  Basket[13] := 3;
+  Basket[14] := 4;
+  Basket[15] := 5;
+  Expected := 102.40;
+
+  fBasket := NewBasket(Basket);
+  assert.AreEqual(Expected, fBasket.Total, MinDelta, format('Total should be %0.2f',[Expected]));
+end;
+
 procedure hpTests.A_basket_with_four_different_books;
 var Basket: TArray<integer>;
     fBasket: IBasket;