c:\test>p1
@a = map[1..3],1..1e6;;
$r = \@a;;

cmpthese -1, {
    a=>q[ ++$a[$_][1]   for 0..$#a ], 
    b=>q[ ++$r->[$_][1] for 0..$#$r ]
};;
    Rate    b    a
b 3.94/s   -- -16%
a 4.72/s  20%   --