Hi, I have an array of strings, some of which are substrings of others, I'd like to remove those "short" string, only keep the longest. The following simple-minded implementation gives an n^2 algorithm. I'm wondering whether there is something faster, like n*log(n). Thanks. 
use strict;

my @data = qw/a mnk ab m b bc abcd cd bcd bd m nk /;
my @result = ();
foreach $a(@data){
    my $is_sub = 0;
    foreach $b(@data){
      $b =~ /$a/i and length($b) != length($a) and $is_sub = 1 and las
+t;
    }
    push @result,$a unless $is_sub;
  }

print join(",",@result);

# output is: mnk,abcd,bd

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In reply to Seeking the longest string in an array by johnnywang

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