DAY9：leetcode #21 Merge Two Sorted Lists

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.

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

class Solution(object):
def mergeTwoLists(self, l1, l2):
"""
:type l1: ListNode
:type l2: ListNode
:rtype: ListNode
"""
head = ListNode(0)
r = head
while True:
if l1 and l2:
if l1.val < l2.val:
temp = ListNode(l1.val)
r.next = temp
r = r.next
l1 = l1.next
else:
temp = ListNode(l2.val)
r.next = temp
r = r.next
l2 = l2.next
elif l1:
temp = ListNode(l1.val)
r.next = temp
r = r.next
l1 = l1.next
elif l2:
temp = ListNode(l2.val)
r.next = temp
r = r.next
l2 = l2.next
else:
break
return head.next