my @nums    = 1 .. 10;
my @results = evens(@nums);

##</code><code>##

sub evens {
  my (@nums) = @_;
  ...;
}

##</code><code>##

sub this_sub_returns_1 {
  return 1;
  2;
}

sub this_sub_returns_2 {
  1;
  2;
}

##</code><code>##

use strict;
use warnings;

# Write a subroutine (&evens) that recieves an array of numbers and returns 
# an array containing only even numbers Give an example of calling the 
# subroutine.

sub even
{
	my (@nums) = @_;
	my @evens;
	foreach my $number (@nums)
	{
		if ($number % 2 == 0)
		{
			push @evens, $number;
		}
	}
	return @evens;
}

print "Results for even(1..10)\n";
print "$_\n" for even( 1 .. 10 );

sub even_better
{
	grep { $_ % 2 == 0 } @_;
}

print "Results for even_better(1..10)\n";
print "$_\n" for even_better( 1 .. 10 );

# Write a subroutine(&squares) that recieves an array of numbers and 
# squares each number in the array. Note: nothing is returned. 

sub square
{
	foreach my $number (@_)
	{
		$number *= $number;
	}
	return;
}

print "Results for square(1..10)\n";
my @nums = 1 .. 10;
square(@nums);
print "$_\n" for @nums;

sub square_better
{
	$_ *= $_ for @_;
}

print "Results for square_better(1..10)\n";
my @nums_better = 1 .. 10;
square_better(@nums_better);
print "$_\n" for @nums_better;