#!/usr/bin/perl
use warnings;
use strict;

use Text::Table;

binmode DATA,   'utf8';
binmode STDOUT, 'utf8';
<DATA> for 1,2; # Throw away the header and the horizontal line.

my %hash;
while (<DATA>) {
    my ($w1, $p1, $w2, $p2) = (split /\|/)[1 .. 4];
    last unless $w2;
    s/^\s+|\s+$//g for $w1, $w2;
    $hash{$w1}{1} = $p1;
    $hash{$w2}{2} = $p2;
}

my $table = 'Text::Table'->new(\'|', 'word', \'|', 'difference', \'|');

for my $word (keys %hash) {
    my $detail = $hash{$word};
    if (exists $detail->{1} and exists $detail->{2}) {
        $table->add($word, $detail->{1} - $detail->{2});
    }
}

print $table->title, $table->rule('-', '+'), $table->body;

__DATA__
| wordF1     | percentageF1 | wordF2       | percentageF2 |
|------------+--------------+--------------+--------------|
| politici   |       0.0489 | politici     |       0.0295 |
| referendum |       0.0238 | consenso     |       0.0126 |
| verità     |       0.0198 | referendum   |      0.00654 |
| scandalo   |       0.0112 | verità       |      0.00526 |
| vergogna   |      0.00723 | tradizionali |      0.00343 |
| corrotto   |      0.00439 | tradizione   |      0.00266 |
| scandali   |      0.00394 | tradizioni   |      0.00234 |
| consenso   |      0.00373 | tradizionale |       0.0022 |
| corrotti   |      0.00332 | scandalo     |      0.00142 |
| propaganda |       0.0027 | vergogna     |      0.00131 |
|------------+--------------+--------------+--------------|