C Language: Macros inside the parameters are error-prone, when used as far as possible parentheses and examples

Macros inside parameters without parentheses error-prone, when used as far as possible parentheses

Program 1:

#include <stdio.h>

#define sqare(X) x*x

int Main ()

{

int n = ten;

int m= Sqare (n);

printf ("m=%d\n", m);

return 0;

}

Results:

m=100

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Analysis: There seems to be no problem, see the following two examples

Program 2:

#include <stdio.h>

#define sqare(X) x*x

int Main ()

{

int m = Sqare (1 + 3); //1+3*1+3=7

printf ("m=%d\n", m);

return 0;

}

Results:

M=7

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Corrective Procedure 2:

#include <stdio.h>

#define sqare(x) (x)* (x )

int Main ()

{

intm =Sqare(1+3);//(1+3)*(1+3)= -

printf ("m=%d\n", m);

return 0;

}

Results:

M=16

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Program 3:

#include <stdio.h>

#define ADD(X) x+x //No parentheses error-prone

int Main ()

{

int m = 10* ADD (2); //10*2+2

printf ("m=%d\n", m);

return 0;

}

Results:

M=22

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Corrective Procedure 3:

#include <stdio.h>

#define ADD(X) (x+x)

int Main ()

{

int Span style= "font-family: ' The new song Body '; Font-size:13px;background:rgb (255,255,255);" > m = 10* add (2); //10* Span style= "font-family: ' New song body '; Color:rgb (0,128,0); Font-size:13px;background:rgb (255,255,255);" > ( 2+2 )

printf ("m=%d\n", m);

return 0;

}

Results:

M=40

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C Language: Macros inside the parameters are error-prone, when used as far as possible parentheses and examples