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1---2-2-1-1-------2-2-1-1-------2-2-1-1-------2-2-1-1-------
2-----------2-2-----------2-2-----------2-2-----------2-2---
3---------------3-------------3-------------3-------------3-
4-----------------------------------------------------------
5-----------------------------------------------------------
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1-----------------------------------------------------------
2---------------1-------------1---------------------------3-
3-------2-2-3-3-------2-2-3-3-------3-3-5-5-6-----3-3-5-5---
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5-----------------------------------------------------------
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1---2-2-1-1-------2-2-1-1-------2-2-1-1-------2-2-1-1-------
2-----------2-2-----------2-2-----------2-2-----------2-2---
3---------------3-------------3-------------3-------------3-
4-----------------------------------------------------------
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3-------2-2-3-3-------2-2-3-3-------3-3-5-5-----
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