how to remove container div of the navigation menu in wordpress

<div class="menu">
<ul>
<li class="page_item page-item-16"><a href="http://localhost/example/home/">Home</a></li>
<li class="page_item page-item-2"><a href="http://localhost/example/sample-page/">Sample Page</a></li>
</ul>
</div>

wp_nav_menu( );

      wp_nav_menu( array( 'container'=> false, 'menu_class'=> false, ) ); 

 wp_nav_menu( array( 'container' => '' ) );