People have posted other solutions. This is probably no worse or no better…

use strict;
use warnings;
use Data::Dump qw/dd/;

my %phrases = (
    'rendition' => '3',
    'automation' => '2',
    'saturation' => '3',
    'mass creation' => 2,
    'automation technology' => 2,
    'automation technology process' => 3,
    'technology process' => 5,
    'automation process' => 2,
);

sub filter_wordlist_thing {
    my %output = %{+shift};
    for my $key (grep / /, keys %phrases) {
        my @words = split / /, $key;
        my @word_combos =
            grep $_ ne $key,
            map join(" ", @words[$_->[0]..$_->[1]]),
            map { my $start = $_; map [$start, $_], $start .. $#words 
+} 0 .. $#words;
        delete @output{@word_combos};
    }
    \%output;
}

dd filter_wordlist_thing(\%phrases);

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toby döt ink

In reply to Re: retain longest multi words units from hash by tobyink
in thread retain longest multi words units from hash by Anonymous Monk

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