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A comment on Counting set bits in an interesting way. Parent comment

Re:Counting set bits in an interesting way by omegalulw on Saturday April 30, 2022 @08:56AM (#31215691)
For those wondering how this works, n & n-1 zeros out the least significant 1. Simply by doing this repeatedly you count the number of 1s.
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Re:Counting set bits in an interesting way by a_e_k on Saturday April 30, 2022 @01:46PM (#31217754)
Right. And the reason that zeroes out the least significant bit is because subtracting one just borrows up to it. E.g., for n = 464:

    n       = 464d 111010000b
    n-1     = 463d 111001111b
    n&(n-1) = 448d 111000000b
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