use strict;
use warnings;
use Data::Dump qw(dump);
use autodie;

my %ave;
open my $in,'<', "testscores.txt";
while (<$in>){
    my ($name, $score) =split /[\s=s,]+/;
    for (0..3){
    $ave{$name}[$_]=$score;
    }
}
#dump \%ave;

get_ave(\%ave); #get it by hash_ref
my %hash_ref;  #why do I have to declare ?
sub get_ave{
    my $hash_ref =@_; #declared here too?
    my %hash=%$hash_ref;
    
    dump \%hash;
    #dump \%hash_ref;
    
    }