• @[email protected]
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        1 year ago

        xor has the property x ^ x = 0, and x ^ 0 = x. So, x ^ x ^ y = y

        a' = a ^ b
        b' = b ^ a' = b ^ (a ^ b) = a
        a'' = (a ^ b) ^ a = b
        

        This is pretty clever, I’ve never seen this for a swap.

        • ActuallyRuben
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          21 year ago

          Couldn’t have explained it better myself. I don’t remember where exactly I first read about this trick, but it’s mainly useful in C or Assembly, as you don’t have to resort to using a third variable/register.