题解 | #合并两个排序的链表#

两个指针分别指向两个链表，cur指针指向目前已排序好链表的末尾，然后两个指针的node去比，cur指向小的那个，小的那个链表指针后移即可。注意下边界条件就行了。

class ListNode:
    def __init__(self, x):
        self.val = x
        self.next = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param pHead1 ListNode类 
# @param pHead2 ListNode类 
# @return ListNode类
#
class Solution:
    def Merge(self, pHead1, pHead2):
        # write code here
        text = ListNode(-1)
        cur = text
        while pHead1 or pHead2:
            if pHead1 == None:
                cur.next = pHead2
                cur = cur.next
                pHead2 = pHead2.next
            elif pHead2==None:
                cur.next = pHead1
                cur = cur.next
                pHead1 = pHead1.next
            elif pHead1.val <= pHead2.val:
                cur.next = pHead1
                cur = cur.next
                pHead1 = pHead1.next
            else:
                cur.next = pHead2
                cur = cur.next
                pHead2 = pHead2.next
        return text.next