finding items that occur more than once in a list

[castironpi at gmail.com]

On Mar 21, 3:39 pm, John Machin <sjmac... at lexicon.net> wrote:
> On Mar 22, 1:11 am, castiro... at gmail.com wrote:
> > A collision sequence is not so rare.
>
> > >>> [ hash( 2**i ) for i in range( 0, 256, 32 ) ]
>
> > [1, 1, 1, 1, 1, 1, 1, 1]
>
> Bryan did qualify his remarks: "If we exclude the case where an
> adversary is choosing the keys, ..."

Some adversary.  What, you mean, my boss or my customers?