浅谈关于C语言中#define的副作用

# include <stdio.h>
# include <stdlib.h>
# define CALL_WITH_MAX(a,b) f((a)>(b)?(a):(b))
int main(void)
{
 int a = 5;
 int b = 0;
 CALL_WITH_MAX(++a,b);
 CALL_WITH_MAX(++a,b+20);
 return 0;
}

# include <stdio.h>
# include <stdlib.h>
# define CALL_WITH_MAX(a,b) f((a) > (b) ? (a):(b))
void f(int x)
{
 printf("compare result = %d\n",x); 
}
int main(void)
{
 int a = 5;
 int b = 0;
 printf("Initial value a = %d\n",a);
 CALL_WITH_MAX(++a,b);
 printf("excute the first a = %d\n\n",a);
 printf("Initial value a = %d\n",a);
 CALL_WITH_MAX(++a,b+20);
 printf("excute the second a = %d\n\n",a);
  
 return 0;
}