#include<stdio.h>

int main()

{

   int size1 = sizeof ;

   int size2 = sizeof();

   int a = ;

   int size3 = sizeof a;

   int size4 = sizeof(a);

   int size5 = sizeof(int);

   int size7 = sizeof(double);

   //int size6 = sizeof int;//错误写法

   printf("sizeof 10 :%d\n",size1);

   printf("sizeof(10):%d\n",size2);

   printf("sizeof a:%d\n",size3);

   printf("sizeof(a):%d\n",size4);

   printf("sizeof(int):%d\n",size5);

   printf("sizeof(double):%d\n",size7);

   return ;

}

sizeof  :

sizeof():

sizeof a:

sizeof(a):

sizeof(int):

sizeof(double):