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

void print_strings(char* label, char** strings, size_t length) {
    printf("\n\n%s\n", label);
    for(size_t i = 0; i < length; i++) {
        printf("%s\n", strings[i]);
    }
    printf("\n");
}

int compare_fn(void const* a_lhs, void const* a_rhs) {
    // return negative if *a_lhs < *a_rhs
    //        zero     if        =
    //        positive if        >
    char* const* a_lhs_str = a_lhs;
    char* const* a_rhs_str = a_rhs;
    return strcmp(*a_lhs_str, *a_rhs_str);
}

int main(int argc, char* argv[]) {
    char* strings[] = { "alpha", "charlie", "foxtrot", "bravo", "echo", "delta" };
    size_t size_of_one = sizeof(strings[0]);  // size of a char* is 8 on our platform
    size_t number_of_elements = sizeof(strings) / size_of_one;
    print_strings("BEFORE sorting", strings, number_of_elements);

    qsort(strings, number_of_elements, size_of_one, compare_fn);
    
    print_strings("AFTER sorting", strings, number_of_elements);
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */