use strict;
use warnings;

my @str = ("j    k l         foobar", "foobar", "jkl foobar", "1 2 3", "jk l foobar", "foobar j k l", "foobar j kl", "           ", " ", "j jk foobar", "j k jk foobar", "j k l");

my @sanitisedNames = ();

for(@str) {
	$_ =~ s/\s+/ /g;

	if ($_ =~ /^\s$/) {
		next;
	}

	my $boundary = &sanitise($_);
	
	my $sanitisedName;
	if ($boundary == 0) {
		$sanitisedName = $_;
	} elsif ($boundary == length($_)) {
		$_ =~ s/\s+//g;
		$sanitisedName = $_;
	} else {
		my $firstPart = substr($_, 0, $boundary);
		$firstPart =~ s/\s+//g;
		my $secondPart = substr($_, $boundary);
		$sanitisedName = $firstPart.' '.$secondPart;
	}

	push(@sanitisedNames, $sanitisedName);
	
}

print $_, "\n" for (@sanitisedNames);

sub sanitise {
	my $str = shift;

	my @chars = split('', $str);

	my $count = 0;
	my $len = length($str);

	while ($count < $len) {
		if ($chars[$count++] ne ' ' && $count < $len && $chars[$count++] eq ' ') {
		} else {
			if ($count == $len) {
				return $len;
			}
			if ($count > 3) {
				$count = $count - 3;
				return $count;
			} else {
				return 0;
			}
		}
	}
}