c++ - I don't understand the working of the following Macro -

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what mathematical equivalent equation of following macro 

#define sq(a) (a*a ) int answer sq(2 + 3 );

output 11 case , 

int answer sq(2 + 4);

is 14 can't figure out equation outputs.

the macro defined lacks brackets keep arithmetic working want. remember preprocessor macros doing text replacement solely. you'll calling shown expands 

int answer (2 + 4 * 2 + 4);

and according operator precedence result 14.

write macro 

#define sq(a) ((a)*(a))

to result expected.


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