use strict;
use warnings;

my @switches = qw /-d -l -m/;
my @values   = qw /-d  disk1 disk2 disk3
                   -l  load1 load2 load3 load4
                   -m  memory1 memory2/;

my %switches;

@switches {@switches} = ();

my $curr;
foreach my $v (@values) {
    if (exists $switches {$v}) {
        $curr = $v;
        next;
    }
    die "Unknown switch: $v\n" unless defined $curr;
    push @{$switches {$curr}} => $v;
}


while (<DATA>) {
    chomp;
    $_ = "-$_";
    if (exists $switches {$_}) {
        if ($switches {$_}) {
            print "Values for $_: @{$switches{$_}}\n";
        }
        else {
            print "$_ does not have values.\n";
        }
    }
    else {
        print "Unknown switch $_\n";
    }
}
    
__DATA__
l
d
m
x

##</code><code>##

Values for -l: load1 load2 load3 load4
Values for -d: disk1 disk2 disk3
Values for -m: memory1 memory2
Unknown switch -x