Help me, how i can echo a category of a single post in single.php???

Thanks, if i use <?php echo wp_get_post_categories( $post_id, $args ); ?> display me the string “array”.

I must add this function in function.php to meke this???

function wp_get_post_categories( $post_id = 0, $args = array() ) {
$post_id = (int) $post_id;

$defaults = array(‘fields’ => ‘ids’);
$args = wp_parse_args( $args, $defaults );

$cats = wp_get_object_terms($post_id, ‘category’, $args);
return $cats;
}

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