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Re: Re: Character Combinations

by Limbic~Region (Chancellor)
on Aug 22, 2003 at 23:06 UTC ( #285953=note: print w/ replies, xml ) Need Help??


in reply to Re: Character Combinations
in thread Character Combinations

chunlou,
Permutations are not combinations. For instance - say I wanted to find all combinations of 4 character strings with each position able to be 26 different letters. This is what I believe is being asked for. I am pretty sure there is an iterative solution - but all I can come up with right now are recursive ones.

Cheers - L~R


Comment on Re: Re: Character Combinations
Re: Re: Re: Character Combinations
by chunlou (Curate) on Aug 22, 2003 at 23:36 UTC
    You mean this?
    use Algorithm::FastPermute; my @c = ('a'..'c'); for my $i (0..2) { for my $j (0..2) { my @c = @c[$i..$j] if $i <= $j; permute {print @c , "\n"} @c; } } __END__ a ab ba abc acb cab bac bca cba b bc cb c
      chunlou,
      Considering that missed ca - no. It also doesn't work if you change
      my @c = ('a'..'c');
      to
      my @c = ('a'..'z');

      Permutations are not combinations.

      L~R

        Silly me. Should have consulted with this: Permutations and combinations.
        use Algorithm::FastPermute; sub combinations { return [] unless @_; my $first = shift; my @rest = combinations(@_); return @rest, map { [$first, @$_] } @rest; } for(combinations('a'..'c')){ my @c = @{$_}; permute {print @c , "\n"} @c; } __END__ c b bc cb a ac ca ab ba abc acb cab bac bca cba

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