#!/usr/bin/perl 

use strict;
use warnings;
use 5.010;

chomp( my @words = <DATA> );
@words = sort { substr( $a, 1, 1 ) cmp substr( $b, 1, 1 ) } @words;
say for @words;

__DATA__
How
about
sorting
an
array
of
words
by
the
second
character
every
word