The challenge is to write a sub that takes the paramters ($length, @symbols) and produces an ordered list of all sequnces of length $length that are combinations of characters from the list @symbols. The output ordering is based on the order of @symbols. Assume that @symbols is a list comprised of any quantity of one-byte ASCII chars.

My current attempt at 52 chars:

sub c{my$n=-1+shift;$n?map{my$c=$_;map$c.$_,c($n,@_)}@_:@_}
[download]

Example:

print join " ", c qw(2 a b c d);
print "\n";
print join " ", c qw(4 0 1);

# outputs
aa ab ac ad ba bb bc bd ca cb cc cd da db dc dd
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 
+1110 1111
[download]

Good luck, and may your efforts yield little code :)

   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

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