category logo

<h1 id="logo">
<?php
$in_news = 0; // set a flag varable to false
  if( is_category() && in_array( '23', get_ancestors( get_query_var('cat'), 'category' ) ) ) $in_news = 1; // set flag to true
  if( is_single() ) {
    $cats = get_the_category();
    foreach ( $cats as $cat ) {
    if( in_array( '20', get_ancestors( $cat, 'category' ) ) ) $in_news = 1; // set flag to true
    }
  }
if( $in_news == 1 || is_category(23)) : ?>
<a href="http://localhost/test"><img width="345" height="176" src="http://localhost/test/wp-content/uploads/logo-old.png"></a>
<?php else : ?>
<a href="http://localhost/test"><img width="345" height="176" src="http://localhost/test/wp-content/uploads/logo.png"></a>
<?php endif; ?>
</h1>