Algorithm to tell if two arrays have identical members

Obvious answers would be:

1. Sort both lists, then check each
   element to see if they’re identical
2. Add the items from one array to a
   hashtable, then iterate through the
   other array, checking that each item
   is in the hash
3. nickf’s iterative search algorithm

Which one you’d use would depend on whether you can sort the lists first, and whether you have a good hash algorithm handy.