ABC140D
https://gyazo.com/8e967088bef468ccfed5f2beb01a1dd3
Thoughts.
The rotation only changes the score for up to four people before and after the end of the row.
The maximum score is when everyone is looking in the same direction.
Add an inward-facing guard at the end.
Rotation does not change the score when the outside of the area is facing a different direction.
Rotation does not change the score even when the inside of the area is oriented differently.
When you have both, your score increases by 2. This is the best move you can make.
Count how many areas can be obtained in linear order (there are two ways to align to the right or to the left, so take the larger one).
The smaller of that number and K multiplied by 2 is the score increment
Official Explanation
approximately the same
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