每日两题 T34

输入:
[
  1->4->5,
  1->3->4,
  2->6
]
输出: 1->1->2->3->4->4->5->6

/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */
/**
 * @param {ListNode[]} lists
 * @return {ListNode}
 */
var mergeKLists = function (lists) {
  let n = lists.length;
  if (n == 0) return null;
  let mergeTwoLists = (l1, l2) => {
    if (l1 == null) return l2;
    if (l2 == null) return l1;
    if (l1.val <= l2.val) {
      l1.next = mergeTwoLists(l1.next, l2);
      return l1;
    } else {
      l2.next = mergeTwoLists(l1, l2.next);
      return l2;
    }
  }
  let merge = (left, right) => {
    if (left == right) return lists[left];
    let mid = (left + right) >> 1;
    let l1 = merge(left, mid);
    let l2 = merge(mid + 1, right);
    return mergeTwoLists(l1, l2);
  }
  return merge(0, n - 1);
};

if (_this.props.onClick) _this.props.onClick(event);

if (!event.defaultPrevented && // onClick prevented default
    event.button === 0 && // ignore everything but left clicks
    !_this.props.target && // let browser handle "target=_blank" etc.
    !isModifiedEvent(event) // ignore clicks with modifier keys
   ) {
  event.preventDefault();

  var history = _this.context.router.history;
  var _this$props = _this.props,
      replace = _this$props.replace,
      to = _this$props.to;


  if (replace) {
    history.replace(to);
  } else {
    history.push(to);
  }
}