1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 | #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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