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Why is x & -x equal to the largest power of 2 that divides x?
Or how to find the largest power of 2 that divides x?
I agree, this is a terrible explanation, but if you contrast with how we represent in base 10, that is, decimal, then it should make sense. Coming back to our original concern, x & -x gives you the largest power of 2 that divides x only when-x is represented in two’s complement. We have a nice mathemagical property involving the largest power of b in base b format.
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