合并两个排序的链表

题目描述
输入两个单调递增的链表，输出两个链表合成后的链表，当然我们需要合成后的链表满足单调不减规则。

python solution:

# -*- coding:utf-8 -*-
class ListNode:
    def __init__(self, x):
        self.val = x
        self.next = None

class Solution:
    # 返回合并后列表
    def Merge(self, pHead1, pHead2):
        new = ListNode(0)
        work = new
        while pHead1 and pHead2:
            if pHead1.val<pHead2.val:
                work.next = pHead1
                work = work.next
                pHead1 = pHead1.next
            else:
                work.next = pHead2
                work = work.next
                pHead2 = pHead2.next
        if pHead1:
            work.next = pHead1
        if pHead2:
            work.next = pHead2
        return new.next