[perl] trim function 구현...

의외로 내장 함수가 없구만..
장난해? ㅋㅋㅋ

# Perl trim function to remove whitespace from the start and end of the string
sub trim($)
{
	my $string = shift;
	$string =~ s/^\s+//;
	$string =~ s/\s+$//;
	return $string;
}
# Left trim function to remove leading whitespace
sub ltrim($)
{
	my $string = shift;
	$string =~ s/^\s+//;
	return $string;
}
# Right trim function to remove trailing whitespace
sub rtrim($)
{
	my $string = shift;
	$string =~ s/\s+$//;
	return $string;
}