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       ÔÚgccÖУ¬ ¶ÔÓÚCÓïÑÔ£¬ÏÂÃæµÄÓï¾äÊǺϷ¨µÄ£º
const int a=0;
int *p=&a;
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           const int a=0£»
           int *p=£¨int *£©&a£»
2.  ¼ÈÈ»Äܹ»½«const±äÁ¿µÄµØÖ·¸³¸øÖ¸Ïò·Çconst±äÁ¿µÄÖ¸Õ룬ÄÇôÄÜ·ñ¸Ä±äͨ¹ýÖ¸Õë¸Ä±äconst±äÁ¿µÄֵĨ£¿
    1)ÔÚgccÖУ¬±àÒëÖ´ÐÐÒÔÏ´úÂ룺
const    int c=2;
      int *p=&c;
      *p=1;
printf("c is :%d\n",c);
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½á¹ûΪ£º
c is 1
 
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     2.½ÓÏÂÀ´¿´ÏÂÃæÒ»¶Î´úÂ룺
#include <stdio.h>
#include <unistd.h>
int main(void)
{
      const   int c=2;
      int a=0;
     
      const int *p;
      p=&a;
     
      int *p2=&a;
      p2[1]=-1;
 
      printf("p2[1] is :%d\n",p2[1]);
      printf("a is :%d\n",a);
      printf("c is :%d\n",c);
      printf("c address is:%d\n",&c);
      printf("p2[1] address is:%d\n",p2+1);
      printf("*(&c) is :%d\n",*(&c));
}
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p2[1] is :-1
a is :0
c is :-1
c address is:-1076230280
p2[1] address is:-1076230280
*(&c) is :-1
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˳ʱÕë·½·¨ ½â¶Á C ¸´ÔӺ궨Òå

[This was posted to comp.lang.c by its author, David Anderson, on 1994-05-06.]
The ``Clockwise/Spiral Rule''
By David Anderson
There is a technique known as the ``Clockwise/Spiral Rule'' which enables any C programmer to parse in their head any C declaration!
There are three simple steps to fo ......

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     int * ptr = (int *)mal ......
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