>>13426354We can have 518 inhabitants with 0, 1, ... , 517 hairs each. If we have n > 518 inhabitants, then the distribution of hair counts yielding the smallest maximal hair count is 0, 1, ... , 517, 519, ... , n + 1, and n + 1 > n, violating (3). So There are at most 518 inhabitants.
>>13426710A knave cannot say they are a knave so B must be lying and is a knave. C is telling the truth and is a knight.