Copy List with Random Pointer LeetCode solution in JavaScript

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var copyRandomList = function (head) {
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  if (!head) return head;
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  let curr = head;
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  // manipulate the Linked List and store a copy node at every nod's next
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  while (curr != null) {
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    let next = curr.next;
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    curr.next = new Node(curr.val);
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    curr.next.next = next;
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    curr = next;
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  }
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  // console.log(head)
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  // Setting random point of copied node according to original node
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  curr = head;
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  while (curr != null && curr.next != null) {
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    if (curr.random) {
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      curr.next.random = curr.random.next;
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    } else {
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      curr.next.random = null;
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    }
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    curr = curr.next.next;
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  }
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  // console.log(head.next.next.next)
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  // break the like made for linking copy node with original node
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  curr = head;
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  let ans = head.next;
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  while (curr != null) {
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    let temp = curr.next;
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    if (temp) {
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      curr.next = temp.next;
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      curr = curr.next;
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    }
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    if (curr) {
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      temp.next = curr.next;
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      temp = temp.next;
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    }
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  }
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  return ans;
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};