my ($filename1, $filename2) = qw( adaykin1.txt adaykin2.txt );
my @string;

for my $fn ($filename1, $filename2) {        # iterate over given filenames
 open my $fh, '<', $fn or die "$fn - $!";    # open each file
 local $/; push @string, <$fh>               # read it into one string
}
# 
print $string[0]; # first file as one big string
print $string[1]; # second file as one big string
...