Using a hash would be better. Try this

my %data;
while(<DATA>){
    chomp;
    my $val = <DATA>;
    chomp($val);
    $data{$_} = $val;
}

use Data::Dumper;
print Dumper \%data;

__DATA__
A
 33
B
 22

__OUTPUT__

$VAR1 = {
          'A' => ' 33',
          'B' => ' 22'
        };
[download]

BUT if you really want to use symbolic reference(which I really advise against) you could use this.

while(<DATA>){
    chomp;
    my $val = <DATA>;
    chomp($val);
    $$_ = $val;
}

print "A: $A\n";
print "B: $B\n";

__DATA__
A
 33
B
 22
[download]