I'm trying to let a user pick which hash to get data from and I think I need to dereference a pointer to do this. Maybe what I have so far will explain better. 
use strict;
use warnings;

my %cs101 = ("joe"=>    "80" );

print "Choose which hash\n";
chomp (my $input = <STDIN>);
#my $whichhash=\%cs101;
my $whichhash="$input";

sub hashvalues {
   while( (my $key, my $value) = each (%$whichhash) ) {
       print "$key $value\n";
   }
}

&hashvalues;

[download]

I want the input to be the hash name- cs101. When I uncomment out the hard coded dereference the output prints as I think it should.

I've tried many variations of ${var} and concatenation to get \% in front of $input.
I've looked at

perldoc -q "pass.*filehandle"

Is that the answer and I just don't get it?

Thank-you.

In reply to Dereference array via STDIN by gctaylor1

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