<?php
function get_page_id()
{
    return isset($_GET["id"]) ? $_GET["id"] : 0;
}

function page_exists($pages, $id)
{
    foreach ($pages as $page) {
        if ($page["id"] == $id) {
            return true;
        }
    }
    return false;
}

function get_article_ids($articleData)
{
    $ids = [ 5 ];
    foreach ($articleData as $value) {
        array_push($ids, $value["id"]);
    }
    return $ids;
}