Mirror Reflection LeetCode solution in JavaScript

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// Time complexity: O(log (min(p,q))
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// Space complexity: O(1)
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var mirrorReflection = function (p, q) {
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  let ext = q,
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    ref = p;
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  while (ext % 2 == 0 && ref % 2 == 0) {
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    ext /= 2;
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    ref /= 2;
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  }
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  if (ext % 2 == 0 && ref % 2 == 1) return 0;
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  if (ext % 2 == 1 && ref % 2 == 1) return 1;
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  if (ext % 2 == 1 && ref % 2 == 0) return 2;
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  return -1;
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};