use strict;
use warnings;

use Test::More qw{ no_plan };
use Benchmark  qw{ cmpthese };

my @animals =  qw{
   tlephane
   lamec
   hellyfisj
   sctopuo
   nuffip
   slbatrosa
   yonkem
   sippopotamuh
   kardvara
   phees
   };

my $expected = join q{:}, qw{
   elephant
   camel
   jellyfish
   octopus
   puffin
   albatross
   monkey
   hippopotamus
   aardvark
   sheep
   };

my %methods = (
   bitStr => sub
      {
          my @words = @_;
          substr( $_, 0, 1)
             ^= substr( $_, -1 )
             ^= substr( $_, 0, 1 )
             ^= substr( $_, -1 )
             for @words;
          return join q{:}, @words;
      },
   reRev => sub
      {
          my @words = @_;
          $_ = join q{}, reverse m{(.)(.*)(.)}
             for @words;
          return join q{:}, @words;
      },
   reSub => sub
      {
          my @words = @_;
          s{(.)(.*)(.)}{$3$2$1}
             for @words;
          return join q{:}, @words;
      },
   slice => sub
      {
          my @words = @_;
          $_ = join q{}, ( split m{} )[ -1, 1 .. length() - 2, 0 ]
             for @words;
          return join q{:}, @words;
      },
   ssBy2s => sub
      {
          my @words = @_;
          ( substr( $_, 0, 1 ), substr $_, -1 ) =
             ( substr( $_, -1 ), substr $_, 0, 1 )
             for @words;
          return join q{:}, @words;
      },
   ssNeg => sub
      {
          my @words = @_;
          substr( $_, 0, 1 ) =
             substr $_, -1, 1, substr $_, 0, 1
             for @words;
          return join q{:}, @words;
      },
   );

foreach my $method ( sort keys %methods )
{
    my $result = $methods{ $method }->( @animals );
    ok( $result eq $expected, $method );
}

cmpthese(
   -3, 
   {
       map {
               my $codeStr =
                  q[sub { my $ref = $methods{ ] .
                  $_ .
                  q[ }->( @animals ); }];
               $_ => eval $codeStr;
       }
       keys %methods
   }
   );

foreach my $method ( sort keys %methods )
{
    my $result = $methods{ $method }->( @animals );
    ok( $result eq $expected, $method );
}
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