Problem A: 不同类型指针的size

请填写以下程序输出(1)(2)(3)(4)(5)处的数字。

#include <stdio.h>

struct str {

};

void func(int a int b){};

int main()

{

  int a = 10;

  char c = 'G';

  struct str x;

  int* ptr_int = &a;

  char* ptr_char = &c;

  struct str* ptr_str = &x;

  void (*ptr_func)(int int) = &func;

  void* ptr_vn = NULL;

  printf("Size of Inte%d bytes\n" sizeof(ptr_int));

  printf("Size of Character Pointer\t:\t%d bytes\n" sizeof(ptr_char));

  printf("Size of Structure Pointer\t:\t%d bytes\n" sizeof(ptr_str));

  printf("Size of Function Pointer\t:\t%d bytes\n" sizeof(ptr_func));

  printf("Size of NULL Void Pointer\t:\t%d bytes" sizeof(ptr_vn));

  return 0;

}

输出：

Size of Integer Pointer        :   (1) bytes

Size of Character Pointer     :   (2) bytes

Size of Structure Pointer     :   (3) bytes

Size of Function Pointer      :   (4) bytes

Size of NULL Void Pointer    :  (5) bytes