sub maxprefix {
  my $p = quotemeta shift;
  for (@_) { chop $p until /^$p/ }
  return $p;
}

##</code><code>##

sub maxprefix {
    my $p = shift(@_);
    for(@_) { chop $p  until /^\Q$p/ }
    return $p;
}

##</code><code>##

sub maxprefix {
  my $s = reverse shift;
  my $p = '';
  for (@_) { $p .= quotemeta chop $s while /^$p/ }
  chop $p;
  return $p;
}

##</code><code>##

print maxprefix("testing","terse","tester","time"),$/;