Fix heading numbering

Author: ntrel

articles/variadic-function-templates.dd

@@ -29,9 +29,9 @@ $(CONSOLE
         language makes possible.
         )
 
-$(H3 $(LNAME2 cpp-solutions, C++ Solutions))
+$(H2 $(LNAME2 cpp-solutions, C++ Solutions))
 
-$(H4 The Standard C++ Solution)
+$(H3 The Overload Solution)
 
         $(P The straightforward way to do this in standard C++
         is to use a series of function templates, one for
@@ -98,7 +98,7 @@ template<class T1, class T2, class T3> void print(T1 a1, T2 a2, T3 a3)
         compilation.
         )
 
-$(H4 C++ Variadic Templates)
+$(H3 C++ Variadic Templates)
 
         $(P C++11 supports variadic templates:
         )
@@ -120,9 +120,9 @@ template<class T, class... U> void print(T a1, U... an)
         A specialization with no arguments ends the recursion.
         )
 
-$(H3 $(LNAME2 d-solutions, D Programming Language Solutions))
+$(H2 $(LNAME2 d-solutions, D Programming Language Solutions))
 
-$(H4 The D Look Ma No Templates Solution)
+$(H3 The D Look Ma No Templates Solution)
 
         $(P It is not practical to solve this problem in C++ without
         using templates. In D, one can because D supports typesafe
@@ -151,7 +151,7 @@ void print(...)
         which give a pointer to the values and their types, respectively.)
         )
 
-$(H4 Translating the Variadic C++ Solution into D)
+$(H3 Translating the Variadic C++ Solution into D)
 
         $(P Variadic templates in D enable a straightforward translation
         of the C++11 variadic solution:
@@ -187,7 +187,7 @@ void print(T, A...)(T t, A a)
         arguments by calling `print()()`.
         )
 
-$(H4 The Static If Solution)
+$(H3 The Static If Solution)
 
         $(P It would be nice to encapsulate all the logic into a
         single function. One way to do that is by using
@@ -213,7 +213,7 @@ void print(A...)(A a)
         from any remaining elements in the original sequence.
         )
 
-$(H4 The Foreach Solution)
+$(H3 The Foreach Solution)
 
         $(P But since sequences can be manipulated like arrays,
         we can use a `foreach` statement to iterate over