use strict;
use warnings;

my @txt = ('cc', 'cz');

for (@txt)
{
    if (m/^(.)\1$/)
    {
        print "True   \$_ = |$_|   \$1 = |$1|\n";
    }
    else
    {
        print "False  \$_ = |$_|   \$1 = |$1|\n";
    }
}