Perl code by skeletonkey - 8 lines

Link:

skeletonkey - Perl, pasted on Oct 17:

my %mymap = (
    one => 1,
    two => 2, 
    three => 3,
    four => 4,
);
my $n = keys %mymap;
print "Number of elements: $n\n";

Output:

1	Number of elements: 4