my($words, %everything);
my @countKey = keys %everything;
my @countValue = values %everything;
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Declare a hash; fill two arrays with the keys and values of the empty hash (i.e., no keys or values).

foreach my $word(split /\s+/, $input) {
    $everything {$word}++; 
    $words++;
}
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Put stuff in the hash.

foreach $word(keys %everything) {
    print "$word was seen $everything{$word} times\n";
}
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Print the keys and values of the now non-empty hash.

print start_table({-border=>1});
print Tr(td('Keys'), td('Values'));
print Tr(td(print("@countKey")), td(@countValue));

print end_table;
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Use the contents of the still empty arrays previously filled from what was an empty hash to build a table.