leetcode.0021. Merge Two Sorted Lists

leetcode.0021. Merge Two Sorted Lists

题目

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

Example:

Input: 1->2->4, 1->3->4
Output: 1->1->2->3->4->4

参考答案（python3）

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution:
    def mergeTwoLists(self, l1, l2):
        """
        :type l1: ListNode
        :type l2: ListNode
        :rtype: ListNode
        """

        result = ListNode(0)
        l = result

        while l1 and l2:
            if l1.val < l2.val:
                l.next = l1
                l1 = l1.next
            else:
                l.next = l2
                l2 = l2.next
            #融合后链表的下一位,当前位置刚刚赋值
            l = l.next

        #把剩余的链表排在后面
        l.next = l1 or l2  
        #返回融合后链表从第二个对象开始，第一个对象是自己创建的ListNode(0)
        return result.next

答案链接