一次性写出C++中的所有关键字，有人会问了，到底有几个呢？  下面来数数吧！

asm            do                 if                   return              try
auto           double             inline               short               typedef
bool           dynamic_cast       int                  signed              typeid
break          else               long                 static              union
case           enum               mutable              static_cast         unsigned
catch          explicit           namespace            struct              using
char           export             new                  switch              virtual
class          extern             register             sizeof              typename
const          false              operator             template            void
const_cast     float              private              this                volatile
continue       for                protected            throw               wchar_t
default        friend             public               true                while
delete         goto               reinterpret_cast