agc026 c

agc026_c

Thoughts.

How much does 18C9 cost...

I can afford 13, and 15 is too much to ask for, so 18 is a no-go.

Added: It was 36C18.

You can always assume that the number is even and the left end is red (since there is always a red-blue inverted one).

Official Explanation

Since the blue letters are N and the right half is also N, we can say "the number of blue letters on the left matches the number of red letters on the right".

If you halve it, you get 2^18, which is okay if you do a full search.

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