Wow, your %scores isn't defined correctly at all.

# perl -l
my %scores = (
   map { $_ =>  1 } qw( A E I L N O R S T U ),
   map { $_ =>  2 } qw( B D G               ),
   map { $_ =>  3 } qw( C M P               ),
   map { $_ =>  4 } qw( F H V W Y           ),
   map { $_ =>  5 } qw( K                   ),
   map { $_ =>  8 } qw( J X                 ),
   map { $_ => 10 } qw( Q Z                 ),
);
print "$_ => $scores{$_}" for keys %scores;
__END__
S => 1
T => 1
N => 1
K => 1
Y => 1
2 => 1
E => 1
Z => 1
J => 1
W => 1
B => 1
H => 1
D => 1
I => 1
10 => 1
G => 1
U => 1
F => 1
V => 1
Q => 1
M => 1
C => 1
L => 1
A => 1
O => 1
3 => 1
X => 1
P => 1
8 => 1
4 => 1
R => 1
5 => 1
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Perhaps this is a good time for parentheses?

my %scores = (
   map( { $_ =>  1 } qw( A E I L N O R S T U ) ),
   map( { $_ =>  2 } qw( B D G               ) ),
   map( { $_ =>  3 } qw( C M P               ) ),
   map( { $_ =>  4 } qw( F H V W Y           ) ),
   map( { $_ =>  5 } qw( K                   ) ),
   map( { $_ =>  8 } qw( J X                 ) ),
   map( { $_ => 10 } qw( Q Z                 ) ),
);
print "$_ => $scores{$_}" for keys %scores;
__END__
[download]