use strict;
use warnings;

my %spelling_of = (
                   1 => 'one',
                   2 => 'two',
                   3 => 'three',
                   );
my @integers = (1, 2);

foreach my $key (sort keys %spelling_of) {
    push @integers, $spelling_of{ $key };
}
printf qq(%s\n), join q(, ), @integers;

@integers = (3, 4, 5);

my $spelling_href = \%spelling_of;
foreach my $key (sort keys %$spelling_href) {
    push @integers, $spelling_href->{ $key };
}
printf qq(%s\n), join q(, ), @integers;

##</code><code>##

1, 2, one, two, three
3, 4, 5, one, two, three

##</code><code>##

use strict;
use warnings;

my %spelling_of = (
                   1 => 'one',
                   2 => 'two',
                   3 => 'three',
                   );
my @integers = (1, 2);
my @spellings = ();

foreach my $integer (@integers) {
    my $spelling = $spelling_of{ $integer };
    push @spellings, (defined( $spelling ) ? $spelling : q(?));
}
printf qq(%s => %s\n),
    join( q(, ), @integers),
    join( q(, ), @spellings),
    ;

@integers = (3, 4, 5);
@spellings = ();

my $spelling_href = \%spelling_of;
foreach my $integer (@integers) {
    my $spelling = $spelling_href->{ $integer };
    push @spellings, (defined( $spelling ) ? $spelling : q(?));
}
printf qq(%s => %s\n),
    join( q(, ), @integers),
    join( q(, ), @spellings),
    ;

__END__