1
45
20
-1
white
+===================|   |===================+
] _________________       _________________ [
]|        |        |     |        |        |[
]|        |        |     |        |        |[
]|________|________|     |________|________|[
]|        |        |     |        |        |[
]|________|________|     |________|________|[
=                                           =
                                             
                                             
                                             
                                             
=                                           =
]                                           [
] _________________                   ______[
]|        |        |                 /   /  [
]|        |        |                /   />  [
]|________|________|               |   />   [
]|________|________|               |  /     [
+===================|   |===================+