Re: Advent of Code 2018 megathread

[cblake]

By the way, if you are trying to "right size" a set or table to streamline 
resizing costs, you can use rightSize(number of members to support). This is 
easier than trying to guess the power of two at which such a population is 
supported for both initSet and initTable. rightSize uses the same formula (its 
inverse, really) as the internal formula used to decide when doubling capacity 
is needed.