Leetcode 23 合并K个排序链表

class Solution {
    public ListNode mergeKLists(ListNode[] lists) {
        PriorityQueue<ListNode>queue=new PriorityQueue<>(new Comparator<ListNode>() {
            public int compare(ListNode o1,ListNode o2){
                return o1.val-o2.val;
            }
        });
        for(int i=0;i<lists.length;i++){
            if(lists[i]!=null){
                queue.add(lists[i]);
            }
        }
        ListNode dummy =new ListNode(-1),cur=dummy;
        while(!queue.isEmpty()){
            ListNode temp =queue.poll();
            cur.next=temp;
            cur=temp;
            if(temp.next!=null){
                queue.add(temp.next);
            }
        }
        return dummy.next;
    }
}

参考:https://blog.youkuaiyun.com/katrina95/article/details/79112038