1
var reverseList = function (head) {
2
  //  Iteratively
3
  [cur, rev, tmp] = [head, null, null];
4
  while (cur) {
5
    tmp = cur.next;
6
    cur.next = rev;
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    rev = cur;
8
    cur = tmp;
9
    //[current.next, prev, current] = [prev, current, current.next]
10
  }
11
};