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

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

int compare_strings(void const* a_lhs, void const* a_rhs) {
    char* const* a_lhs_str = a_lhs;
    char* const* a_rhs_str = a_rhs;
    char* lhs_str = *a_lhs_str;
    char* rhs_str = *a_rhs_str;
    if(strcmp(lhs_str, rhs_str) < 0) {  // ex:  "alpha", "bravo"
        return -1;
    }
    else if(strcmp(lhs_str, rhs_str) == 0) {  // ex:  "alpha", "alpha"
        return 0;
    }
    else {  // ex: "bravo", "alpha"
        return 1;
    }
}

int main(int argc, char* argv[]) {
    char const* strings[] = { "charie", "bravo", "echo", "delta", "alpha" };

    size_t size_of_one = sizeof(strings[0]);
    size_t num_elements = sizeof(strings) / sizeof(strings[0]); // for static arrays ONLY
    print_strings("BEFORE SORT", strings, num_elements);

    qsort(strings, num_elements, size_of_one, compare_strings);

    print_strings("AFTER SORT", strings, num_elements);

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

© Copyright 2021 Alexander J. Quinn         This content is protected and may not be shared, uploaded, or distributed.