Is there any known algorithm that can generate a shuffled range [0..n) in linear time and constant space (when output produced iteratively), given an arbitrary seed value?
Assume n may be large, e.g. in the many millions, so a requirement to potentially produce every possible permutation is not required, not least because it's infeasible (the seed value space would need to be huge). This is also the reason for a requirement of constant space. (So, I'm specifically not looking for an array-shuffling algorithm, as that requires that the range is stored in an array of length n, and so would use linear space.)
I'm aware of question 162606, but it doesn't present an answer to this particular question - the mappings from permutation indexes to permutations given in that question would require a huge seed value space.
Ideally, it would act like a LCG with a period and range of n
, but the art of selecting a
and c
for an LCG is subtle. Simply satisfying the constraints for a
and c
in a full period LCG may satisfy my requirements, but I am wondering if there are any better ideas out there.
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