C-Preprocessor

[krishnapratapcool]

hi ..i m krishna..
can u give me the reason of not getting the output as according to precedence in the below program.....

#include<stdio.h>
#define SQUARE(x) x*x
void main()
{
float s=10,u=30,t=2, a;
a=2*(s-u*t)/SQUARE(t);
printf("result=%f",a)
}

output i m getting on TurboC compiler is == -100.0000
but by pecedence of ' * ' and ' / ' it should be == -25.0000

[JosAH]

hi ..i m krishna..
can u give me the reason of not getting the output as according to precedence in the below program.....

#include<stdio.h>
#define SQUARE(x) x*x
void main()
{
float s=10,u=30,t=2, a;
a=2*(s-u*t)/SQUARE(t);
printf("result=%f",a)
}

output i m getting on TurboC compiler is == -100.0000
but by pecedence of ' * ' and ' / ' it should be == -25.0000

I moved your article to the C/C++ forums. The C/C++ articles section is for articles
only, not questions.

To answer your question both * and / have equal precedence and they're both
left associative. The remedy in your case to put parentheses around your
macro definition (which is a sensible thing to do in most if not all cases).

#define SQUARE(x) ((x)*(x))
 

kind regards,

Jos

ps. before I forget: welcome to TSDN.