Fleshing your code out a little into a full example gives:

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__
gr an df at he rj
dp or te rj kv ap
la ne ts ca pe ww

[download]
$ARRAY1 = [
            ( 0 ) x 13,
            1,
            0,
            1,
            ( 0 ) x 3,
            1,
            ( 0 ) x 32,
            1,
            ( 0 ) x 30,
            1,
            ( 0 ) x 9,
            1,
            ( 0 ) x 79,
            1,
            ( 0 ) x 12,
            1,
            ( 0 ) x 94,
            1,
            ( 0 ) x 4,
            1,
            ( 0 ) x 55,
            1,
            ( 0 ) x 38,
            1,
            ( 0 ) x 12,
            1,
            ( 0 ) x 56,
            1,
            ( 0 ) x 46,
            1,
            ( 0 ) x 13,
            1,
            ( 0 ) x 81,
            1,
            ( 0 ) x 81
          ];

[download]

Note in particular that the line @bigram_list{@bigram_list} = (); becomes @bigram_list{@testBigrams} = (0) x @testBigrams; and starts to make some sense.

DWIM is Perl's answer to Gödel

In reply to Re^2: Identifying bigrams and making a note of which ones exist by GrandFather
in thread Identifying bigrams and making a note of which ones exist by lampros21_7

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