链表归并排序

---

title: 链表归并排序

categories:

• 链表
• 算法

tags:

• 链表
• 归并排序
• 算法
• 排序

---

链表归并排序

用一张图来说明归并排序:

代码

# Definition for singly-linked list.
class ListNode(object):
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next
class Solution(object):
    # fixme: 归并排序(自底向上合并链表)
    def merge(self, node1, node2):
        dummy = ListNode()
        pre = dummy
        while node1 is not None and node2 is not None:
            if node1.val <= node2.val:
                pre.next = node1
                pre = pre.next
                node1 = node1.next
            else:
                pre.next = node2
                pre = pre.next
                nod