How to Hide DropInBlog Admin Menus

function plt_hide_dropinblog_menus() {
	//Hide the "DropInBlog" menu.
	remove_menu_page('dropinblog-settings');
	//Hide the "DropInBlog → Settings" menu.
	remove_submenu_page('dropinblog-settings', 'dropinblog-settings');
	//Hide the "DropInBlog → Manage Posts" menu.
	remove_submenu_page('dropinblog-settings', 'https://app.dropinblog.com/posts');
}

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

Where do I put this code?