Limit Number of Sticky Posts to Show

limit-sticky-posts.php

<?php
    $sticky = get_option( 'sticky_posts' );

    /* Sort the newest one at the top */
    rsort( $sticky );

    /* Get the 2 newest stickies (change 2 for a different number) */
    $sticky = array_slice( $sticky, 0, 2 );

    /* Query Post */
    $args = array(
        'post_type'      => array( 'post' ),
        'post__in'       => $sticky,
        'ignore_sticky_posts' => 2
    );
    
    query_posts($args);
?>

    <!-- Output Html Here -->
    
<?php endif; wp_reset_query(); ?>

where should I add this code to control the number of sticky posts on homepage?