Yep. Went and tried the lookup method against a 5 step parallel shift and add me... | Hacker News

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		monocasa on Oct 13, 2016 \| parent \| context \| favorite \| on: Google's “Director of Engineering” Hiring Test Yep. Went and tried the lookup method against a 5 step parallel shift and add method (which is the fastest bitwise way I know of without, and the lookup is ~5% faster than the bitwise way. https://gist.github.com/monocasa/1d44a03cbd0170bfffc6a4a5c37...

gcp on Oct 13, 2016 [–]

Your code has 6 shifts, 6 adds/subs and 6 ANDs.

You can do it with 4 shifts, 3 adds, 1 MUL and 4 ANDs.

Your code is simply suboptimal.

monocasa on Oct 13, 2016 | [–]

For a 64bit quantity? I'm curious to see your algorithm in actual code.

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