我需要我的菜单如下所示:
| Menu 1 | -> | Sub menu of menu 1 - 1 |
| Menu 2 | | Sub menu of menu 1 - 2 |
| Menu 3 | | Sub menu of menu 1 - 3 |
| Menu 1 | | Sub menu of menu 2 - 1 |
| Menu 2 | -> | Sub menu of menu 2 - 2 |
| Menu 3 | | Sub menu of menu 2 - 3 |
| Menu 1 | | Sub menu of menu