<?php
$token = '3bbe0c487729de7ee8d3f52b11c9118a1681ac119c2178c29e561d44b9be9a5ff5b53e7e356dedca60c76';
$clubs = array(18203014);
$user_id = 79490249;
$message = " ввввв))) ";

echo '<pre>';
foreach ($clubs as $club) {
    $posts = json_decode(file_get_contents('https://api.vk.com/method/wall.get?count=100&owner_id=-'.$club.'&filter=others&v=5'), true);
    foreach ($posts['response']['items'] as $post) {
        if ($post['from_id'] == $user_id) {
            print_r(json_decode(file_get_contents('https://api.vk.com/method/wall.delete?owner_id=-'.$club.'&post_id='.$post['id'].'&v=5&access_token='.$token), true));
        }
    }
    print_r(json_decode(file_get_contents('https://api.vk.com/method/wall.post?owner_id=-'.$club.'&v=5&message='.urlencode($message).'&access_token='.$token), true));
    echo '<pre>';
}
?>