题目:
Sort a linked list in O(n log n) time using constant space complexity.
Example 1:
Input: 4->2->1->3 Output: 1->2->3->4
Example 2:
Input: -1->5->3->4->0 Output: -1->0->3->4->5
思路:
就是先将链表表示的数据用列表表示,然后用列表的排序函数进行排序。再将排好序的列表转回成链表的形式返回!
代码:
# Definition for singly-linked list. # class ListNode: # def __init__(self, x): # self.val = x # self.next = None class Solution: def sortList(self, head): """ :type head: ListNode :rtype: ListNode """ l = list() p = head while p: l.append(p.val) p = p.next l.sort() p = newhead = ListNode(-1) for i in l: p.next = ListNode(i) p = p.next return newhead.next