math is hard (to remember)

cabney cabney at
Thu Jul 12 23:59:57 CDT 2001

On 12 Jul 2001, Randal L. Schwartz wrote:

> Here's one way that involves more recursion than iteration.  I've come
> up with ways that involve more iteration than recursion too. :)

hmmm, something like this?? (this is very nice, thanks again. :)

#! /usr/bin/perl -w

my @list = qw(red orange yellow green blue);

my @ans = combo(@list);
print "@{$_}\n" for @ans;

sub combo
	my $ret;
	while ( @_ )
		my $this = shift;
		my @redo;
		for $done (@{$ret})
			push @redo, [$this,@{$done}];
		push @{$ret}, [$this], @redo;


	return @{$ret};

There was a time
A wind that blew so young
For this could be the biggest sky
And I could have the faintest idea


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