initial commit

2025-11-17 13:49:43 +01:00
commit ac8bd4c5d7
1 changed files with 79 additions and 0 deletions
--- a/index.php
+++ b/index.php
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 <!DOCTYPE html>
 <html lang="en">
 <head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Primzahlen</title>
    <style>
        .wrapper {
            display: flex;
            flex-direction: row;
            gap: 20px;
        }
    </style>
 </head>
 <body>
 <h1>Primzahlenberechnung</h1>
 <div class="wrapper">
    <div>
        <form action="index.php" method="post">
            <label>Input:
                <input type="number" name="input">
            </label>
            <button type="submit">Berechnen</button>
        </form>
        <?php
        if(isset($_POST['input'])) {
            $primeNumbers = [];
            $max = (int) $_POST['input'];
            for($i = 0; $i <= $max; $i++) {
                if(isPrime($i)) {
                    $primeNumbers[] = $i;
                }
            }
            echo "<h3>Primzahlen von " . htmlspecialchars($_POST["input"], ENT_QUOTES, 'UTF-8') . " sind:</h3>";
            foreach($primeNumbers as $number) {
                echo "<span>" . $number . "</span><br>";
            }
        }
        function isPrime($i) {
            if ($i <= 1) return false;
            if ($i <= 3) return true;
            if ($i % 2 == 0) return false;
            for ($j = 3; $j * $j <= $i; $j += 2) {
                if ($i % $j == 0) {
                    return false;
                }
            }
            return true;
        }
        ?>
    </div>
    <div>
        <h3>Logarithmische Funktion (n = 1..100)</h3>
        <div class="mono">
            <?php
            for ($n = 1; $n <= 100; $n++) {
                $ln = log($n);
                $lnFormatted = number_format($ln, 4, '.', '');
                $starsCount = (int) floor($ln);
                $stars = $starsCount > 0 ? str_repeat('*', $starsCount) : '-';
                echo sprintf("%3d: ln=%6s  %s<br>", $n, $lnFormatted, $stars);
            }
            ?>
        </div>
    </div>
 </div>
 </body>
 </html>