Use a Trie. 

sub insert {
  my $trie=shift;
  my $str=shift;
  $trie=$trie->{$_}||={}
    foreach (split //,$str);
}
sub common {
  my $trie=shift;
  my $common="";
  while (1==scalar keys %$trie) {
      my $char=(keys %$trie)[0];
      $common.=$char;
      $trie=$trie->{$char};
  }
  $common;
}
my %trie;
insert(\%trie,$_) foreach qw(model4run1 model2run1 model4run2 model1ru
+n1);
print common(\%trie);

[download]

But it could be argued I have Trie's on my brain. :-)


---
demerphq

<Elian> And I do take a kind of perverse pleasure in having an OO assembly language...

In reply to Re: Find common prefix from a list of strings by demerphq
in thread Find common prefix from a list of strings by Albannach

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