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

#define log_int(n) printf("%s == %d\n", (#n), (n));
#define log_addr(n) printf("%s == %p\n", (#n), (void*) (n));
int main(int argc, char* argv[]) {
    const int num1 = 5;
    
    log_int(num1);
    // num1 is read only
    // num1 = 7;

    const int* a_num = &num1;
    // data inside a_num is also read only
    // *a_num = 8;
    log_addr(a_num);
    log_int(*a_num);

    const int num2 = 7;
    a_num = &num2;
    log_addr(a_num);
    log_int(*a_num);

    int num3 = 9;
    a_num = &num3;
    log_addr(a_num);
    log_int(*a_num);
    num3 = 17;
    // even though num3 can be modified, and a_num
    // currnetly is the address of num3, we are still
    // not allowed to modify *a_num
    //*a_num = 12;
    log_addr(a_num);
    log_int(*a_num);

    int num4 = *a_num;
    log_int(num4);
    num4 = 12;
    log_int(num4);
    log_int(*a_num);

    int* const const_a_num = &num3;
    log_addr(const_a_num);
    log_int(*const_a_num);
    *const_a_num = 12;
    log_int(*const_a_num);
    const_a_num = &num4;
    log_addr(const_a_num);

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

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