OpenBSD-4.6/regress/usr.bin/tsort/normalize-cycles

#!/usr/bin/perl

# Written by Marc Espie, 2001.
# Public domain

@cycle = ();

sub show_cycle()
{
	return if @cycle == 0;
	$min = 'zzzzz';
	for ($i = 0; $i < @cycle; $i++) {
		if ($cycle[$i] lt $min) {
			$minindex = $i;
			$min = $cycle[$i];
		}
	}
	@ordered=();
	for ($i = $minindex; $i <@cycle; $i++) {
		push(@ordered, $cycle[$i]);
	}
	for ($i = 0; $i < $minindex; $i++) {
		push(@ordered, $cycle[$i]);
	}
	print join(',', @ordered), "\n";
}
	
while (<>) {
	chomp;
	if ($_ eq 'tsort: cycle in data') {
		show_cycle();
		@cycle = ();
	} else {
		m/^tsort:\s+/ and push(@cycle, $');
	}
}
show_cycle();