Hold your plucked chicken, Diogenes. Note the "evenly distributed" requirement. This is not. But in general, sure, there's a lot of hash functions that aren't

Hold your plucked chicken, Diogenes. Note the "evenly distributed" requirement. This is not. But in general, sure, there's a lot of hash functions that aren't great. f(x)=x is one, that's actually even seen in the wild. Java's Integer class does that for its hashCode() function, and it even does a passable job of indexing a hash table.