This is insanely clever! ++

Though I agree with using the term "iterator" for this snippet, it is worth noting that the space requirement grows at least1 as ~ log(N)(2N-1)2, so it is not an "iterative algorithm" (whose space requirements would be constant).

1I write "at least" because I haven't the foggiest idea of what perl is doing under the hood with glob; for all I know, it pre-computes all 2N -1 elements and dishes them out one by one.

Update: Added a missing log factor to my estimate for the space requirement; it arises from the fact that the number of digits per element grows logarithmically with N.

the lowliest monk

In reply to Re: Glob powerset with progressive ordering by tlm
in thread Glob powerset with progressive ordering by Roy Johnson

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