use strict;
use warnings;
use Data::Dump::Streamer;

my @bigram = ( 'aa' .. 'zz' ); # magic!
my @testBigrams = split ' ', do {local $/; <DATA>;};

# make a "set" of the ones in the list:
my %bigram_list;
@bigram_list{@testBigrams} = (0) x @testBigrams;

# corresponds to (and same size as) @bigram.
my @bigrams_existing =
  map { exists $bigram_list{$_} ? 1 : 0 } @bigram;

Dump (\@bigrams_existing);

__DATA__
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