my %hash; my $key;
while ($_= <$file>) {
    my @line= split;
    while (@line) {
        my $part= shift @line;
        if ($part=~/^\D/) { #does not begin with a number
            $key= $part; $hash{$key}=[];
        }
        else {
            $hash{$key}= split /,/,$part;
        }
    }
}