index.php

<?php

require_once('SolutionInterface.php');

$problem = isset($_GET['problem']) && ctype_digit($_GET['problem']) ? $_GET['problem'] : null;

ini_set('max_execution_time', 180);
ini_set('Display_errors', 'on');
error_reporting(E_ALL ^ E_NOTICE);

if ($problem == null) {
    // Show small index
    $dirList = glob('[0-9]*', GLOB_ONLYDIR);
    sort($dirList, SORT_NUMERIC);

    echo '<h1>Problem overview</h1>';
    echo '<ul>';
    foreach ($dirList as $dir) {
        echo '<li><a href="./?problem=' . $dir . '">Problem #' . $dir . '</a>';
    }
    echo '</ul>';
} else if ($problem != null && is_dir($problem)) {
    $solutionFile = $problem . '/Solution.php';
    if (file_exists($solutionFile)) {
        require_once($solutionFile);


        $solution = new Solution();

        // benchmark execution time
        $start = microtime(true);
        echo $solution->solve();
        $end = microtime(true);

        echo '<p>Execution time: ' . round($end - $start, 3) . 's</p>';
    } else {
        echo 'Problem not implemented yet';
    }
} else {
    echo 'This particular Euler problem has not been solved yet';
}