Sort List

Problem

题意：链表排序

code:(nLogn)

 struct ListNode {     int val;     ListNode *next;     ListNode(int x) : val(x), next(NULL) {} };class Solution {    priority_queue<int,vector<int>,greater<int> > q;public:    ListNode *sortList(ListNode *head) {        ListNode *tmp = head;        while(tmp){            q.push(tmp->val);            tmp = tmp->next;        }        tmp = head;        while(tmp){            tmp->val = q.top();            q.pop();            tmp = tmp->next;        }        return head;    }};