You'd have to be careful with this - if it's a picture gallery, a single user will appear to "hit" the site 1+N(number of pictures) time within a very short period of time.

s**lil*;  $*=join'',sort split q**;  s;.*;grr; &&s+(.(.)).+$2$1+; $; =
qq-$_-;s,.*,ahc,;$,.=chop for split q,,,reverse;print for($,,$;,$*,$/)
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