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Hint #2 for Playfair Cipher
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Using the same methods for trying to locate the crib RED PENGUIN FRENZY, we note that it can be segmented either as

	RE DP EN GU IN FR EN ZY

	-R ED PE NG UI NF RE NZ Y-

If it's the first way and positioned at the beginning, we get:

	VY TE SY ED LU TE RV LF
	RE DP EN GU IN FR EN ZY

This is impossible, because the TE repeated in the ciphertext does not match a repeated digraph in the plaintext. Similarly, if the recognition phrase is at the end, we get:

	AR LI TF LA BF FZ CY FU UF BG
	RE DP EN GU IN FR EN ZY EN DX

	AR LI TF LA BF FZ CY FU UF BG
	-R ED PE NG UI NF RE NZ YE ND

In either case, as with the previous crib, the FU/UF near the end is not the encryption of a reversed pair of plaintext letters. This means the recognition phrase appears in the middle of the text, either as

	ST OP RE DP EN GU IN FR EN ZY ST OP

	-S TO PR ED PE NG UI NF RE NZ YS TO P-

Again, there is no repeated ST OP in the cryptogram, so the first segmentation does not work. However, the second segmentation, with its repeated TO in the plaintext, does have one good match point in the cryptogram, about halfway through:

	ET OL QA DF HS FZ WN AI DS MU RU OL HR
	-S TO PR ED PE NG UI NF RE NZ YS TO P-

We can use this to reconstruct most of the square. The TO->OL pairs tell us that TOL are adjacent in a row or column, perhaps wrapping around past the end of the row or column; similarly with EDF. If HS and PE are at opposite corners of a rectangle:

	H..P
	....
	E..S

and FZ and NG are at opposite corners of a rectangle:

	F..N
	....
	G..Z

then it's quite likely that the EDF is part of a column, and we can see all five letters of that column already: EDF, G, and H. Still stumped? Have a look at the Playfair cipher solution.

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