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2-----0-0-0-----0-0-0-----0-----0----0--
3-0-2-------0-2-------0-2---0-2---0-2---
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1---------------------------------------
2-----4--4-2---------------------------0
3-0-2------------4-4-----4-2-0-------2--
4------------2-2-----2-2-------3-3-3----
1---------------------------------------
2-----------0-0-0-2-4-2-------------0---
3-0-0-0-2-4-------------0-0-0-2-4-2-----
4---------------------------------------