Disaster occured!
Christine the waitress was hired to wait tables at a wedding where the guests had their pick between fish or meat, but all the invitations for Table-13 had been misplaced! Not one person in the kitchen had any idea how many of what dish had been ordered, much less who had ordered what! Panic spread across the kitchen as dinner-time approached, but Christine was, in fact, not completely clueless!
For instance, she knew all of the guests were either zealously Christian, refusing to speak a single word unless they knew for certain what they said was unambiguously the truth; or pathological liars, so addicted to deceit they were unable to say anything unless they knew for sure it was the untruth.
She also managed to remember that all zealously Christian guests had ordered the meat only if the two people sitting next to them had ordered the same thing as each other, and had ordered the fish only if the person on their right had ordered a different course from the person on their left. By remarkable coincidence the patheological liars displayed completely opposite behaviours! Christine drew a map of how the guests at Table-13 were placed:

After interviewing the guests briefly she managed to come up with some info that might prove useful:
BILLY: Everyone in this table ordered the fish.
ELLEN: I most certaintly did not order whatever Billy is having!
ANNA: Half the people here ordered the fish, the other half ordered meat.
DANIEL: Don't believe a word Ellen says. She is definitely lying!
FLORA: It's funny how all the people who ordered the meat are sitting together in a row!

Can Christine use this information in order to deduce what everyone ordered in time for dinner to be prepared?

http://nickofalltrades.blogspot.co.uk/2014/12/wedding-whoopsies.html