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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

int main(int argc, char* argv[]) {
    int n = 5;
    int* a_n = &n;   // Declare a variable 'a_n' as type int* (address of an int) and
                     // initialize it to &n (address of n).
    int** a_a_n = &a_n;   // Declare a variable 'a_a_n'
                          // as type int** (address of an address of an int) and
                          // initialize it to &a_n (address of a_n).

    // Adding & to a variab*le adds a '*' to its type.
    // Ex:  If n is an int, then &n is an int*.
    // Ex:  If a_n is an int*, then &a_n is an int**.
    
    printf("n == %d\n", n);
    printf("*a_n == %d\n", *a_n);
    printf("**a_a_n == %d\n", **a_a_n);
    // Q:  Do we need a void* for the printf(…) above?
    // A:  No.  *a_n has type int.  **a_a_n also has type int.
    //     We only need (void*) if the argument is an address type.
    
    printf("&n     == %p\n", (void*)(&n));
    printf("a_n    == %p\n", (void*)a_n);
    printf("*a_a_n == %p\n", (void*)(*a_a_n));
    printf("\n");
    printf("a_a_n  == %p\n", (void*)a_a_n);
    printf("&a_n   == %p\n", (void*)(&a_n));
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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