Why will # elif defined at the back of the output is 3 d, delete, and then don't delete the output is 2 d
Why not just use the SECOND behind and # elif, and add a defined?
Consult!!!!!!

CodePudding user response:

# define statement, d is behind in use should be combined with d,

https://www.cnblogs.com/droidxin/p/3446451.html

CodePudding user response:

Because the English have things
Define and defined are different meanings
Define a macro definition
Have defined macro definition

# ifdef is the abbreviation of the if define
# elif is the abbreviation of else if
SECOND directly, unclear meaning, SECOND is ignored

CodePudding user response:

The same layer of macro definition are best to stick on the left write