 .

         .

               ___
              |   |
           ___|...|___
          |3v :   :4  |
          |___:___:___|
           ___
          |^  |
          |...|___         ___
          |   :^  |       |   |
       ___|...:___|    ___|...|___
      |   :   :   |   |   :   :   |
      |...:...:...|   |...:...:...|
      |   :   :   |   |   :   :   |
      |___:...:___|___|___:...:___|                        ___
          |2  :  |   |   |:   |                       |   |
          |...:___|,,,|,,,|...:___|___ ___ ___ ___ ___ ___|...|
          |  : :  :  :   :   :   :   :   :   :^  :   :   |
          |___:___:,,,:,,,:___:___:___:___:___:___:...:___:___|
                  |   |   |                       |   |
                  |___|___|                       |...|
                                                  |^  |
                                                  |___|
                                           ___ ___ ___ ___ ___
                                          |   :   :v  :   :   |
                                          |___:___:...:___:___|
                                                  |   |
                                               ___|...|___
                                              
                                               ___:___:___

 - (, , 2 ) [ ].
-  (, , 2 )

1 -   (!, !,  ).
2 -  (, , 1 ,  ) [   ],  (2 ) [  ].
3 -   (,  , , 2   ,    ) [ ,  ].
4 -   (,  , 1 ,  ) [ ]