LeetCode23 合并k个排序链表

 1 /**
 2  * Definition for singly-linked list.
 3  * struct ListNode {
 4  *     int val;
 5  *     ListNode *next;
 6  *     ListNode(int x) : val(x), next(NULL) {}
 7  * };
 8  */
 9 
10 struct Status{
11     int val;
12     ListNode* ptr;
13     bool operator< (const Status &comp) const{
14         return val>comp.val;
15     }
16 };
17 
18 class Solution {
19 public:
20     ListNode* mergeKLists(vector<ListNode*>& lists) {
21         priority_queue<Status> q;
22         for(auto node:lists){
23             if(node!=nullptr)
24                 q.push({node->val,node});
25         }
26         ListNode head,*tail=&head;
27         while(!q.empty()){
28             auto temp=q.top();
29             q.pop();
30             if(temp.ptr->next!=nullptr)
31                 q.push({temp.ptr->next->val,temp.ptr->next});
32             tail->next=temp.ptr;
33             tail=tail->next;
34         }
35         return head.next;
36     }
37 };