my @ary =  (
   [1, 2, 3], [1, 1, 0],
   [3, 4, 5], [0, 1, 0],
   [0, 2, 4], [1, 2, 1],
);

my (@arystrings, %aryhash);

for my $ary ( @ary ) {
    $aryhash{$ary} = $ary;
    push @arystrings, scalar $ary; # same string as the key above
}

my %fred = @arystrings; # treats @arystrings as (key,value,key,value,...) list

print_stuff();

%fred = reverse %fred; # reverse hash
print_stuff();

sub print_stuff {
    for my $k (keys %fred) {
        print "$k element 0: '",$aryhash{$k}->[0],"'\n";
        print "array: (",join(",",@{$aryhash{$k}}),")\n";
    }
}
__END__
ARRAY(0x25e6998) element 0: '1'
array: (1,2,3)
ARRAY(0x2603b80) element 0: '3'
array: (3,4,5)
ARRAY(0x260f948) element 0: '0'
array: (0,2,4)
ARRAY(0x260f8d0) element 0: '0'
array: (0,1,0)
ARRAY(0x260f9c0) element 0: '1'
array: (1,2,1)
ARRAY(0x2603a60) element 0: '1'
array: (1,1,0)