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Hint for Double Playfair Cipher
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This cipher is quite difficult with the amount of information available here. Wartime cryptanalysts expected to be able to solve for the keywords after 150 to 200 plaintext-ciphertext pairs were established. Solving this problem probably requires trial and error to guess the correct period for segmenting the message, and also to guess which key was re-used.

The second square of the Double Playfair used one of the keys listed as possible duplicates: BRIGHTONROCK, in left-to-right rows. The period chosen is 15, so that the cipher is broken up into pairs thus:
	TIPPOYNOYBYAKLP
	YNKQTESIOORKSSP

	ZDASPMMPNPYITQB
	COYLOXNPXTCTYYO

	ZBGPSZCXCQLICDP
	RIMLEKTRRGEKRMP

	RBXYQMATFMXYLQI
	TNWWGDYGVFESLNI

	GWQGENDNODMPTXK
	IRIFVGNIBTDTYNB

	UEWPPS
	XMPKWT
This means the last groups correspond to:
	-MESSA
	GEENDS
See the rest of the Double Playfair cipher solution.

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