tasks a-s

Task/Set/Ada/set.ada

@@ -0,0 +1,54 @@
+with Ada.Text_IO, Ada.Containers.Ordered_Sets;
+
+procedure Set_Demo is
+
+   package CS is new  Ada.Containers.Ordered_Sets(Character); use CS;
+   package IO renames Ada.Text_IO;
+
+   -- helper functions for string to something conversion, and vice versa
+        function To_Set(S: String) return Set is
+           Result: Set;
+        begin
+           for I in S'Range loop
+              begin
+                 Result.Insert(S(I));
+                 -- raises Constraint_Error if S(I) is already in Result
+              exception
+                 when Constraint_Error => null;
+              end;
+           end loop;
+           return Result;
+        end To_Set;
+
+        function Image(S: Set) return String is
+           C: Character;
+           T: Set := S;
+        begin
+           if T.Is_Empty then
+              return "";
+           else
+              C:= T.First_Element;
+              T.Delete_First;
+              return C & Image(T);
+           end if;
+        end Image;
+
+        function Image(C: Ada.Containers.Count_Type) return String renames
+          Ada.Containers.Count_Type'Image;
+
+   S1, S2: Set;
+begin -- main program
+   loop
+      S1 := To_Set(Ada.Text_IO.Get_Line);
+      exit when S1 = To_Set("quit!");
+      S2 := To_Set(Ada.Text_IO.Get_Line);
+      IO.Put_Line("Sets [" & Image(S1) & "], [" & Image(S2) & "] of size"
+                    & Image(S1.Length) & " and" & Image(S2.Length) & ".");
+      IO.Put_Line("Intersection:   [" & Image(Intersection(S1, S2)) & "],");
+      IO.Put_Line("Union:          [" & Image(Union(S1, S2))        & "],");
+      IO.Put_Line("Difference:     [" & Image(Difference(S1, S2))   & "],");
+      IO.Put_Line("Symmetric Diff: [" & Image(S1 xor S2) & "],");
+      IO.Put_Line("Subset: "  & Boolean'Image(S1.Is_Subset(S2))
+                  & ", Equal: " & Boolean'Image(S1 = S2) & ".");
+   end loop;
+end Set_Demo;