Greetings, PerlMonks!

I'm trying to figure out if foreach is faster than grep with map. I've replaced grep and map in a large script with foreach and noticed a substantial speed improvement, so my guess is that it is faster. However, I'd like to verify that somehow.

With the two scripts below, am I comparing the same things and not apple to oranges? Or have I misunderstood grep and map?

#!/usr/bin/perl

use strict;
use warnings;

my @c = (1 .. 10000000);

my @d;
foreach my $dd (@c) {
    push(@d, $dd % 2);
}

my @e;
foreach my $ee (@d) {
    if (!$ee) {
        push(@e, $ee);
    }
}

exit(0);
[download]

The script above is much faster than the one below, according to time.

#!/usr/bin/perl

use strict;
use warnings;

my @c = (1 .. 10000000);

my @d = map( $_%2, @c);

my @e = grep(/0/, @d);

exit(0);
[download]

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