use strict;
use warnings;

use Benchmark qw( cmpthese );

my @a = map { int rand 10 } 1..100;
my @b = map { int rand 10 } 1..100;

sub perl_for {
   my $dummy_load;
   for my $i (reverse 0..$#a) {
      $dummy_load = $a[$i] . ' ' . $b[$i];
   }
   1;
}

sub c_style_for {
   my $dummy_load;
   for (my $i=@a; $i--; ) {
      $dummy_load = $a[$i] . ' ' . $b[$i];
   }
   1;
}

sub while_loop {
   my $dummy_load;
   my $i = @a;
   while ($i--) {
      $dummy_load = $a[$i] . ' ' . $b[$i];
   }
   1;
}

sub ickyb0d {
   my $dummy_load;
   for my $i (0..$#a) {
      $dummy_load = $a[$#a-$i] . ' ' . $b[$#a-$i];
   }
   1;
}

sub ickyb0d_ {
   my $dummy_load;
   for (0..$#a) {
      my $i = $#a-$_;
      $dummy_load = $a[$i] . ' ' . $b[$i];
   }
   1;
}

sub diotalevi {
   my $dummy_load;
   for my $i (1..@a) {
      $dummy_load = $a[-$i] . ' ' . $b[-$i];
   }
   1;
}

cmpthese(-3, {
   perl_for    => \&perl_for,
   c_style_for => \&c_style_for,
   while_loop  => \&while_loop,
   ickyb0d     => \&ickyb0d,
   ickyb0d_    => \&ickyb0d_,
   diotalevi   => \&diotalevi,
});