Non-neutrality

Neobeo My neutral OTPs got destroyed last year; all that's left are the non-neutral ones. Hint: Out of all the 2^272 possible OTPs, almost 4.83% of these have exactly half the bits set. Looking at our 65536 messages, we find that 52.5% have odd parity and 47.5% have even parity. This tells us something about the parity of our flag, and in fact means that we can remove all messages of the former type as it provides no information. Keep doing this to learn the probabilities of each bit being set.