Task: Compare length of two strings

C: #include <stdio.h>
#include <stdlib.h>
#include <string.h>

int cmp(const int* a, const int* b)
{
    return *b - *a; 
}

void compareAndReportStringsLength(const char* strings[], const int n)
{
    if (n > 0)
    {
        char* has_length = "has length";
        char* predicate_max = "and is the longest string";
        char* predicate_min = "and is the shortest string";
        char* predicate_ave = "and is neither the longest nor the shortest string";

        int* si = malloc(2 * n * sizeof(int));
        if (si != NULL)
        {
            for (int i = 0; i < n; i++)
            {
                si[2 * i] = strlen(strings[i]);
                si[2 * i + 1] = i;
            }
            qsort(si, n, 2 * sizeof(int), cmp);

            int max = si[0];
            int min = si[2 * (n - 1)];

            for (int i = 0; i < n; i++)
            {
                int length = si[2 * i];
                char* string = strings[si[2 * i + 1]];
                char* predicate;
                if (length == max)
                    predicate = predicate_max;
                else if (length == min)
                    predicate = predicate_min;
                else
                    predicate = predicate_ave;
                printf("\"%s\" %s %d %s\n",
                    string, has_length, length, predicate);
            }

            free(si);
        }
        else
        {
            fputs("unable allocate memory buffer", stderr);
        }
    }
}

int main(int argc, char* argv[])
{
    char* list[] = { "abcd", "123456789", "abcdef", "1234567" };

    compareAndReportStringsLength(list, 4);

    return EXIT_SUCCESS;
}






PHP: <?php


function retrieveStrings()
{
    if (isset($_POST['input'])) {
        $strings = explode("\n", $_POST['input']);
    } else {
        $strings = ['abcd', '123456789', 'abcdef', '1234567'];
    }
    return $strings;
}


function setInput()
{
    echo join("\n", retrieveStrings());
}


function setOutput()
{
    $strings = retrieveStrings();


    $strings = array_map('trim', $strings);
    $strings = array_filter($strings);

    if (!empty($strings)) {
        usort($strings, function ($a, $b) {
            return strlen($b) - strlen($a);
        });
        $max_len = strlen($strings[0]);
        $min_len = strlen($strings[count($strings) - 1]);
        foreach ($strings as $s) {
            $length = strlen($s);
            if ($length == $max_len) {
                $predicate = "is the longest string";
            } elseif ($length == $min_len) {
                $predicate = "is the shortest string";
            } else {
                $predicate = "is neither the longest nor the shortest string";
            }
            echo "$s has length $length and $predicate\n";
        }
    }
}

?>


<!DOCTYPE html>
<html lang="en">

<head>
    <style>
        div {
            margin-top: 4ch;
            margin-bottom: 4ch;
        }

        label {
            display: block;
            margin-bottom: 1ch;
        }

        textarea {
            display: block;
        }

        input {
            display: block;
            margin-top: 4ch;
            margin-bottom: 4ch;
        }
    </style>
</head>


<body>
    <main>
        <form action=<?php echo $_SERVER['SCRIPT_NAME'] ?> method="post" accept-charset="utf-8">
            <div>
                <label for="input">Input:
                </label>
                <textarea rows='20' cols='80' name='input'><?php setInput(); ?></textarea>
                </label>
            </div>
            <input type="submit" value="press to compare strings">
            </input>
            <div>
                <label for="Output">Output:
                </label>
                <textarea rows='20' cols='80' name='output'><?php setOutput(); ?></textarea>
            </div>
        </form>
    </main>
</body>

</html>