Re: Learning recursion with hailstone seqence

Maarten Wiltink wrote:

1. Can this function be optimised ? (approx 2^67 iterations are
neccessary on current dataset)


It's tail-recursive. You can rewrite it as a loop. Other than that,
there really isn't much room for optimisation - it's a very short
and easy function.

Perhaps using shorter values or using MMX in some way, but I'm not
qualified to say anything about that.

That's all correct, but...

I'd simply wait a few (hundred) years, until a dramatically faster technology becomes available. When a single iteration is performed at 4 GHz, the loop will terminate in about 2000 years.

As a raw guess, I'd predict that the result will be near 42 ;-)

DoDi
.

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