#include<stdio.h>
#define a (x+1)
int x = 2;
void b() {int x = 1;printf("b()  a is %d\n",a);}
void c() {printf("c()2  a is %d\n",a);}
main()
{
	b();
	int x =9;
	x++;
	c();
}
不过乍一看会容易粗心的~~~~~~~~~~