最近看c++標準的時候看到了，據說只能在gnu c++下編譯通過
三字符組和可選指令組
附圖好了
If either of the characters ’ or \, or either of the character sequences /* or // appears in a q-charsequence
or a h-char-sequence, or the character " appears in a h-char-sequence, the behavior is undefined.
Table 3—keywords
asm do if return typedef
auto double inline short typeid
bool dynamic_cast int signed typename
break else long sizeof union
case enum mutable static unsigned
catch explicit namespace static_cast using
char export new struct virtual
class extern operator switch void
const false private template volatile
const_cast float protected this wchar_t
continue for public throw while
default friend register true
delete goto reinterpret_cast try
