Merge k Sorted Lists LeetCode solution in JavaScript

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var mergeKLists = function (lists) {
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  // Use min heap to keep track of the smallest node in constant time.
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  // Enqueue and dequeue will be log(k) where k is the # of lists
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  // b/c we only need to keep track of the next node for each list
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  // at any given time.
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  const minHeap = new MinPriorityQueue({ priority: (item) => item.val });
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  for (let head of lists) {
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    if (head) minHeap.enqueue(head);
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  }
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  // Create tempHead that we initiate the new list with
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  // Final list will start at tempHead.next
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  const tempHead = new ListNode();
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  let curr = tempHead;
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  while (!minHeap.isEmpty()) {
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    const { val, next } = minHeap.dequeue().element;
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    curr.next = new ListNode(val);
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    curr = curr.next;
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    if (next) minHeap.enqueue(next);
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  }
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  return tempHead.next;
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};