C语言 指向指针的指针

int **pr;

Variable num has address: XX771230
Address of Pointer pr1 is: XX661111
Address of Pointer pr2 is: 66X123X1

#include <stdio.h>
int main()
{
     int num=123;

     //A normal pointer pr2
     int *pr2;

     //This pointer pr2 is a double pointer
     int **pr1;

     /* Assigning the address of variable num to the
      * pointer pr2
      */
     pr2 = #

     /* Assigning the address of pointer pr2 to the
      * pointer-to-pointer pr1
      */
     pr1 = &pr2;

     /* Possible ways to find value of variable num*/
     printf("\n Value of num is: %d", num);
     printf("\n Value of num using pr2 is: %d", *pr2);
     printf("\n Value of num using pr1 is: %d", **pr1);

     /*Possible ways to find address of num*/
     printf("\n Address of num is: %p", &num);
     printf("\n Address of num using pr2 is: %p", pr2);
     printf("\n Address of num using pr1 is: %p", *pr1);

     /*Find value of pointer*/
     printf("\n Value of Pointer pr2 is: %p", pr2);
     printf("\n Value of Pointer pr2 using pr1 is: %p", *pr1);

     /*Ways to find address of pointer*/
     printf("\n Address of Pointer pr2 is:%p",&pr2);
     printf("\n Address of Pointer pr2 using pr1 is:%p",pr1);

     /*Double pointer value and address*/
     printf("\n Value of Pointer pr1 is:%p",pr1);
     printf("\n Address of Pointer pr1 is:%p",&pr1);

     return 0;
}

Value of num is: 123
Value of num using pr2 is: 123
Value of num using pr1 is: 123
Address of num is: XX771230
Address of num using pr2 is: XX771230
Address of num using pr1 is: XX771230
Value of Pointer pr2 is: XX771230
Value of Pointer pr2 using pr1 is: XX771230
Address of Pointer pr2 is: 66X123X1
Address of Pointer pr2 using pr1 is: 66X123X1
Value of Pointer pr1 is:  66X123X1
Address of Pointer pr1 is: XX661111

num == *pr2 == **pr1
&num == pr2 == *pr1
&pr2 == pr1