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NuitDuHack 2014 Crypto Write Ups

Carbonara We are given the following ciphertext: %96 7=28 [email protected] E9:D 492= :D iQx>[email protected] xF=:FD r26D2C s:GFDQ] A simple shift shows interesting results: ciphertext = "%96 7=28 [email protected] E9:D 492= :D iQx>[email protected] xF=:FD r26D2C s:GFDQ]" size = len(ciphertext) for i in range(0,100): result="" for c in ciphertext: if ord(c) > 126 or ord(c) < 33: result += c else: first = ord(c)+i if first > 90: first = 64 + (first - 90) result += chr(first) print(result) Here is were the history classes prove valuable, flag is: