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

// okay to copy/adapt these macros
#define log_int(n) printf("%s == %d\n", (#n), n)
#define log_addr(n) printf("%s == %p\n", (#n), (void*)n)

void swap(int** a_a_left, int** a_a_right) {
    int* a_left_num = *a_a_left;
    int* a_right_num = *a_a_right;

    *a_a_left = a_right_num;
    *a_a_right = a_left_num;
}

int main(int argc, char* argv[]) {
    int n1 = 5;
    int n2 = 27;

    log_int(n1);
    log_int(n2);

    int* a_n1 = &n1;
    int* a_n2 = &n2;
    log_addr(&n1);
    log_addr(&n2);
    log_addr(a_n1);
    log_addr(a_n2);
    log_int(*a_n1);
    log_int(*a_n2);
    swap(&a_n1, &a_n2);
    printf("Swap called\n");
    // did not swap
    log_int(n1);
    log_int(n2);
    log_addr(&n1);
    log_addr(&n2);
    // did swap
    log_addr(a_n1);
    log_addr(a_n2);
    log_int(*a_n1);
    log_int(*a_n2);

    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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