------------------0-------------------------------0---------------------------
--------1--------------1----------------1--------------1----------------------
---0---------0--------------0-----0----------0--------------0-----0-----------
-------------2--------------2----------------2--------------2-----------------
--------3--------------3----------------3--------------3----------------------
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---1----1----1----1----0----1----3----0---------------------------------------
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--------2--------------0----2-------------------3----3------------------------
---3--------------3--------------2--------------2-----------------------------
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---0---------3----0--------------0---------3----0-----------------------------
--------0--------------0----0---------0--------------0----0-------------------
--------3--------------3--------------3--------------3------------------------
---2--------------2--------------2--------------2-----------------------------
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---0----0----0----0---------0----1---------1----1-----------------------------
-----------------------2--------------0---------------------------------------
--------3-----------------------------2---------------------------------------
---2--------------2--------------3--------------3-----------------------------
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