回複：回複：回複：回複：經典老智力題

來源: 於 2010-01-31 18:17:57 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

The first guy guesses the color that is the mod-2 sum of all the rest. He has 50% chance of being right. The other 99 guys can deduce their own color based on observation and the previous guys' answers.