#! perl -slw
use strict;

sub clean {
    my( @dirty ) = @_;
    my @clean;
    for ( @dirty ) {
    	s[\s*(\S+)\s*][$1];
    	push @clean, $_;
    }
	return @clean;
}

sub double {
	my( @data ) = @_;
	my @doubled;
	for ( @data ) {
		push @doubled, $_ *2;
	}
	return @doubled;
}

open FILE, '<', 'data\1millionlines.dat' or die $!;
my @data = <FILE>;
my @cleaned = clean( @data );
my @doubled = double @cleaned;
print for @doubled;
printf 'Check mem.'; <STDIN>;

##</code><code>##

#! perl -slw
use strict;

sub clean {
    my( $dirty ) = @_;
    s[\s*(\S+)\s*][$1] for @$dirty;
}

sub double {
	my( $data ) = @_;
	$_ *= 2 for @$data;
}

open FILE, '<', 'data\1millionlines.dat' or die $!;
my @data = <FILE>;
clean( \@data );
double( \@data );
print for @data;
printf 'Check mem.'; <STDIN>;

##</code><code>##

perl -nlwe" m[s*(\S+)\s*] and print $1*2" data\1millionlines.dat