Posted to tcl by miguel at Fri Jun 20 15:59:32 GMT 2008view raw
- Gnomes agree that the first one will say "white" if he sees an even number of whites,
- "black" if he sees an odd number. He has 50% chance of survival.
- The second knows that his hat is black if he sees the same parity as the first, white if the
- parity changed: survives with 100%. All others update the "current parity" to take this info
- into account.
- So: every gnome but the first knows the parity of white hats
- (a) including his, by having updated the initial info with every answer
- (b) excluding his, by looking