I was looking for code to print all the combinations of a set taken two at a time. Looking here, I found
code to print all the permutations of a list. I took that, bent it to my will, and came up with what's below.
It works as I want, I am just wondering if this could be done better or more efficently.
--SparkeyG
#!/usr/bin/perl
my @list = (1 .. 5);
my $take = 2;
comb(\@list, $take, []);
sub comb {
my @items = @{ $_[0] };
my $group = $_[1];
my @list = @{ $_[2] };
unless ($group) {
print "@list\n";
} else {
my (@newitems,@newlist,$i);
foreach $i (0 .. $#items) {
@newlist = @list;
push (@newlist, shift (@items));
@newitems = @items;
comb([@newitems], $group - 1, [@newlist]);
}
}
}
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