#!/usr/bin/perl
use Modern::Perl;

# 934820

my $palindrome_re = qr{
    \b
    (?<pal>          # A palindrome is a sandwich...
        (?<char>\w)  # starting with white bread...
        (?:          # filled with either...
            \w?      #   peanut butter (maybe)...
        |            # or...
            (?&pal)  #   another sandwich...
        )
        \k<char>     # topped off with white bread!
    )
    \b
}ix;

my @Rev_arr = qw /Research tattarrattat Kanakanak Qaanaaq Foobarblivitz/;
for my $word(@Rev_arr) {
	 if ($word =~ /$palindrome_re/) { 
		say $word; 
	 } else {
		say "$word is NOT a palindrome";
	}
}

##</code><code>##

C:\>934820.pl
Research is NOT a palindrome
tattarrattat
Kanakanak
Qaanaaq
Foobarblivitz is NOT a palindrome

C:\>