All these solutions contain the same essential steps, but the first one (no recursion) has no unnecessary extras.

The only way I can imagine doing better on long-term performance would be for a persistent program to maintain previously requested results in a hash, which can be looked up instead of calculated; but that seems way overkill.

One world, one people

In reply to Re: Tail-recursion in perl?! by anonymized user 468275
in thread Tail-recursion in perl?! by neniro

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