C/C ++ key points (4)

 

Master the C/C ++ points (3 ).

 

12. macro definition

I have not paid much attention to the following 3.1 cases. At least I did not know before, but these three points are very important. Only macros that meet these three requirements are correct, otherwise, it may be different from the original meaning of the macro. Here we take it as a separate section to highlight its importance. In future programming, we should strictly define macros according to this form.

 

(1) parameters in the expression are enclosed in parentheses;

(2) enclose Each subexpression in parentheses based on the Operation priority;

(3) enclose the entire expression in parentheses.

For example:

 

# Define MAX (x, y) (x)> (y ))? (X) :( y) // do not add points

From tht's column