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

#define log_addr(n) printf("%s == %p\n", (#n), (void*) (n));
#define log_str(n) printf("%s == \"%s\"\n", (#n), (n));
int main(int argc, char* argv[]) {
    char const* str = "Hello World";
    log_str(str);
    
    char const** a_str = &str;
    // constsant is **a_str
    log_addr(a_str);
    log_str(*a_str);
    *a_str = "Goodbye";
    log_str(*a_str);
    // *a_str can be modified, **a_str cannot
    //**a_str = 'H';
    log_str(*a_str);

    char stack_str[] = "Hello";
    char* a_stack_str0 = stack_str;
    char * const* a_constant_str = &a_stack_str0;
    // constant is *a_constant_str
    log_addr(a_constant_str);
    log_str(*a_constant_str);
    // cannot change *a_constant_str
    //*a_constant_str = "Goodbye";
    log_str(*a_constant_str);
    **a_constant_str = 'Y';
    log_str(*a_constant_str);

    char const* const* a_fully_const_str = &str;
    // constant is **a_fully_const_str and
    // *a_fully_const_str
    log_addr(a_fully_const_str);
    log_str(*a_fully_const_str);
    // both const means I cannot modify
    // *a_fully_const_str or **a_fully_const_str
    //*a_fully_const_str = "Goodbye";
    //**a_fully_const_str = 'H';
    
    // subtle discards a const
    //a_str = &a_stack_str0;
    //log_addr(a_str);
    //log_str(*a_str);
    
    char ** const a_const_str = &a_stack_str0;
    // const is a_const_str
    log_addr(a_const_str);
    log_str(*a_const_str);
    **a_const_str = 'A';
    log_str(*a_const_str);
    *a_const_str = "Goodbye";
    log_str(*a_const_str);
    a_const_str = &a_stack_str0;


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

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