Decode XORed Permutation LeetCode solution in JavaScript

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var decode = function (encoded) {
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  const n = encoded.length + 1;
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  const perm = Array(n);
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  for (let i = 1; i <= n; i++) {
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    perm[0] ^= i;
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  }
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  for (let i = 1; i < n - 1; i += 2) {
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    perm[0] ^= encoded[i];
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  }
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  for (let i = 1; i < n; i++) {
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    perm[i] = perm[i - 1] ^ encoded[i - 1];
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  }
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  return perm;
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};