my @array1 = ('lots', 'of', 'nice', 'words');
my @array2 = ('red','clothes', 'are', 'fun');

my($i, $lastidx) = (0, $#array1);
my @concat_array;

push @concat_array, $array1[$i] . $array2[$lastidx - $i++]
  while $i <= $lastidx;

print "concatenated array: @concat_array";

__output__

concatenated array: lotsfun ofare niceclothes wordsred