<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
    xmlns:image="http://www.google.com/schemas/sitemap-image/1.1"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9
        http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd
        http://www.google.com/schemas/sitemap-image/1.1
        http://www.google.com/schemas/sitemap-image/1.1/sitemap-image.xsd">
    <% @topics.each do |(id, slug, bumped_at, updated_at, posts_count)| %>
      <url>
        <loc><%= build_sitemap_topic_url(slug, id, posts_count) %></loc>
        <lastmod><%= (bumped_at || updated_at).xmlschema %></lastmod>
      </url>
    <% end %>
</urlset>