How to Hide the "vjoon WP Adapter" Admin Menu

function plt_hide_vjoon_wp_adapter_menus() {
	//Hide the "Settings → vjoon WP Adapter" menu.
	remove_submenu_page('options-general.php', 'vj_wp_adapter_settings');
}

add_action('admin_menu', 'plt_hide_vjoon_wp_adapter_menus', 11);

Where do I put this code?