6 +-------------------------------------------------------------------------------------------+   
    |      +            +                                                   +            +      |   
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  5 |-+                                                                     A                 +-|   
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  4 |-+                                                                   ###                 +-|   
    |                                                                 ####   #                  |   
    |                                                             ####       #                  |   
    |                                                        #####            #                 |   
    |                                                    ####                  #                |   
    |                                                ####                       #               |   
  3 |-+                 A                       #####                           #             +-|   
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    |                              #####                                           #            |   
    |                          ####                                                #            |   
    |                      ####                                                     #           |   
  2 |-+    A           ####                                                          #   A    +-|   
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    |            ##                                                                    #        |   
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  1 |-+    ##                                                                            #    +-|   
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    |      +            +                                                   +            +      |   
  0 +-------------------------------------------------------------------------------------------+   
          aaa          bbb                                                 ccc          ddd