DZone Snippets: duplicates code http://snippets.dzone.com/posts Mon, 08 Sep 2008 00:26:45 GMT DZone Snippets: duplicates code Efficient 'uniq' snippet http://snippets.dzone.com/posts/show/152 This snippet will quickly uniq an unsorted array; in other words, remove duplicates. (note: for large arrays, it may be more efficient to sort the array first and simply keep track of consecutive dups instead of using a hash.) <br /> <br /><code> <br /> # Input: @list <br /> # Output: @uniqed <br /> my %u = (); <br /> @uniqed = grep {defined} map { <br /> if (exists $u{$_}) { undef; } else { $u{$_}=undef;$_; } <br /> } @list; <br /> undef %u; <br /></code> <br /> <br /> Wed, 13 Apr 2005 03:26:57 GMT http://snippets.dzone.com/posts/show/152 jmason (Justin Mason)