Add/highest power of 2 #195
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vcnovaes
requested review from
Panquesito7,
raklaptudirm and
appgurueu
as code owners
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Please, merge it under hacktoberfest |
1 similar comment
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Please, merge it under hacktoberfest |
appgurueu
reviewed
Oct 16, 2023
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This seems at least partially redundant with #193:
- Given this, can't I implement
nextPowerOf2(n)ashighestPowerOf2(n) << 1, with the exception ofn == highestPowerOf2(n)being handled specially (not shifting in that case)? - This also goes the other way, so
highestPowerOf2could be implemented in terms ofnextPowerOf2as well.
The more general "bit twiddling" primitive between both of these is count leading zeros (clz). What if you just implemented that instead?
appgurueu
reviewed
Oct 16, 2023
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| export const highestPowerOf2 = (n: number) => { | ||
| let result = 0; | ||
| for (let i = n; i >= 1; i--) { |
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This loop seems somewhat sketchy, given that it only reduces n by one in each iteration. Linear runtime in n is not acceptable, this should be logarithmic in n (and thus linear in the number of bits).
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Find the highest power of two smaller or equal a given number n