$file = fopen ('text_' .$a. '.txt', 'a');

<?php

    ini_set ('max_execution_time', 0);
    
    if (! $_POST) {
    
        echo '<form method="post">URL: <input type="text" name="url" style="width: 200px"> <input type="submit" values="парсить"></form>';
        
    } else {
    
        $vip = file_get_contents ($_POST['url']);
        $n = preg_match_all ('!<span class=title><a href=(.*)>.*</a></span></p>!i', $vip, $result);
        
        if ($n)    {
            for($a=0; $a < $n; $a++) {
                $page = file_get_contents("http://lenta.ru".$result[1][$a]);
                $page = preg_replace ("!<a.*>!isU", ' ', $page);
                $page = str_replace ('</a>', ' ', $page);
                $regex = preg_match_all('!<H2>(.*)</H2>.*</TABLE>(.*)<P class=links>!isU', $page, $itog, PREG_SET_ORDER);
                
                if ($regex) {                    
                    $html .= '<h2>' . $itog[0][1] . "</h2>\n";
                    $html .= str_replace ('<p>', '', $itog[0][2]) . "\n";
                }

            }
            
            // php5
            file_put_contents (date ('H-i') . '.html', $html);
        }
        

    }

?>

$page = preg_replace ("!<a.*>!sU", ' ', $page);

$page = preg_replace ("!<a.*>!isU", ' ', $page);