Здравейте,

Ето това са моите варианти на задачите от първата лекция Introduction to PHP and Apache Web Server. Не съм използвал конзолата, защото не съм и фен и направо съм ги писал за web.

/* 4. Largest Number Again
Having in mind the considerations in the Task 3, find the largest number, but this time the input numbers might contain negatives. */

$numArr = [3, 7, -4, 5];
$stringNumbers = implode(', ', $stringNumbers);

echo "The greatest number from numbers $stringNumbers is: " . max($numArr) . '<br />';

$numArr = [-3, -2, -17, -33, -1];
$stringNumbers = implode(', ', $numArr);

echo "The greatest number from numbers $stringNumbers is: " . max($numArr);

/* 5. Count Letters
You will receive a single line from the standard input containing a word (or at least a set or characters). 
You need to print on the standard input how many times each letter is found in order of the letter appearance, 
in format {letter} -> {times} */

$word = 'apple';
$lettersArr = str_split($word);
$resultArr = [];

foreach ($lettersArr as $key => $letter) {
    if (!array_key_exists($letter, $resultArr)) {
        $resultArr[$letter] = 0;
    }
    $resultArr[$letter]++;
}

foreach ($resultArr as $k => $v) {
    echo $k . ' -> ' . $v . "<br />";
}

/* 6. Count Letters – Sorted
As in Task 5, but the output should be sorted by the times a letter has occurred in descending order, 
then in order of appearance. */

$word = 'apple';
$lettersArr = str_split($word);
$resultArr = [];

foreach ($lettersArr as $key => $letter) {
    if (!array_key_exists($letter, $resultArr)) {
        $resultArr[$letter] = 0;
    }
    $resultArr[$letter]++;
}
arsort($resultArr);

foreach ($resultArr as $k => $v) {
    echo $k . ' -> ' . $v . "<br />";
}

Останалите задачи(7, 8, 9 и 10) съм ги събрал в една, защото те реално надграждат.

PHP кода:

<?php

if (isset($_GET['filter'])) {
    $delimiter = $_GET['delimiter'];
    $names = trim(
        preg_replace('/ +/', ' ',
            preg_replace('/[^A-Za-z0-9 ]/', ' ',
                urldecode(
                    html_entity_decode(
                        strip_tags(
                            $_GET['names']
                        )
                    )
                )
            )
        )
    );
    $ages = trim(
        preg_replace('/ +/', ' ',
            preg_replace('/[^A-Za-z0-9 ]/', ' ',
                urldecode(
                    html_entity_decode(
                        strip_tags(
                            $_GET['ages']
                        )
                    )
                )
            )
        )
    );

    // Insert into db
    if (!empty($names) && (!empty($ages))) {
        $connection = mysqli_connect('127.0.0.1','bobby','123456', 'students');

        if (!$connection) {
            die("Connection failed: " . mysqli_connect_error());
        }

        $query = "INSERT INTO students (Name, Age)
                  VALUES (" . "'" . $names . "'" . ",$ages)";

        if (mysqli_query($connection, $query)) {
            echo "<p style='color: green;'>New record created successfully</p>";
        } else {
            echo "Error: " . $query . "<br>" . mysqli_error($connection);
        }
        mysqli_close($connection);
    }
}

// Get data from db
$connection = mysqli_connect('127.0.0.1','bobby','123456', 'students');

if (!$connection) {
    die("Connection failed: " . mysqli_connect_error());
}

if (isset($_GET["itemsPerPage"])) {
    $recordsPerPage  = $_GET["itemsPerPage"];
} else {
    $recordsPerPage = 3;
}

if (isset($_GET["page"])) {
    $page  = $_GET["page"];
} else {
    $page = 1;
}

$startFrom = ($page-1) * $recordsPerPage;


if (isset($_GET['over18'])) {
    $query = "SELECT * FROM students WHERE Age >= 18";
} else {
    $query = "SELECT * FROM students LIMIT $startFrom, $recordsPerPage";
}

$result = mysqli_query ($connection, $query); //run the query

$totalRecords = "SELECT * FROM students";
$totalResult = mysqli_query($connection, $totalRecords); //run the query
$totalRecords = mysqli_num_rows($totalResult);  //count number of records
$totalPages = ceil($totalRecords / $recordsPerPage);

$prevPage =  ($page > 1) ? '<a href="?itemsPerPage=' . $recordsPerPage . '&page=' . ($page - 1) . '" title="Previous page">[Previous]</a>' : '<span style="display: none;">[Previous]</span>';
$nextPage = ($page < $totalPages) ? '<a href="?itemsPerPage=' . $recordsPerPage . '&page=' . ($page + 1) . '" title="Next page">[Next]</a>' : '<span style="display: none;">[Next]</span>';

if (!mysqli_query($connection, $query)) {
    echo "Error: " . $query . "<br>" . mysqli_error($connection);
}
mysqli_close($connection);


include_once 'problem7-frontend.php';

Таблицата в базата:

CREATE TABLE `students` (
 `Name` varchar(50) NOT NULL,
 `Age` int(3) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8

page.js:

var query = window.location.search.substring(1);
var param = query.split("&");

$(function() {
    $('a[href="?' + param[0] + '&' + param[1] + '"]:first').addClass("active");
});

problem7-frontend.php:

<script src="http://code.jquery.com/jquery-latest.min.js" type="text/javascript"></script>
<script src="page.js" type="text/javascript"></script>
<link rel="stylesheet" type="text/css" href="style.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<div class="container">
    <div class="col-md-10 col-md-offset-1">
        <form method="get">
            <div>
                Delimiter:
                <select name="delimiter">
                    <option value=",">,</option>
                    <option value="|">|</option>
                    <option value="&">&</option>
                </select>
            </div>
            <div>
                Names:
                <input type="text" name="names"/>
            </div>
            <div>
                Ages:
                <input type="text" name="ages"/>
            </div>
            <div>
                Records Per Page:
                <select name="itemsPerPage">
                    <option value="3">3</option>
                    <option value="6">6</option>
                    <option value="9">9</option>
                </select>
            </div>
            <div>
                Show only over 18 years old:
                <input type="checkbox" name="over18">
            </div>
            <div>
                <input type="submit" name="filter" value="Filter!"/>
            </div>
        </form>
        <table class="table table-striped table-condensed table-bordered table-rounded">
            <thead>
                <tr>
                    <th>Names</th>
                    <th>Ages</th>
                </tr>
            </thead>
            <tbody>
                <?php while ($row = mysqli_fetch_assoc($result)): ?>
                    <tr>
                        <td width="20%"><?= $row['Name']; ?></td>
                        <td width="20%"><?= $row['Age']; ?></td>
                    </tr>
                <?php endwhile; ?>
            </tbody>
        </table>
        <div class="align-center">
            <?= $prevPage; ?>
            <?php for ($i = 1; $i <= $totalPages; $i++): ?>
            <a href='?itemsPerPage=<?= $recordsPerPage; ?>&page=<?= $i; ?>' >[<?= $i; ?>]</a>
            <?php endfor; ?>
            <?= $nextPage; ?>
        </div>
    </div>
</div>

Не са най-добрите решения на света, но работят. Очаквам вашите мнения и препоръки.

Поздрави!