链表类
class ListNode:
def __init__(self, x):
self.val = x
self.next = None
两个链表相加
def add_two_nums(l1, l2):
l = head = ListNode(0)
carry = 0
while l1 or l2 or carry:
v1 = v2 = 0
if l1:
v1 = l1.val
l1 = l1.next
if l2:
v2 = l2.val
l2 = l2.next
carry, val = divmod(v1+v2+carry, 10)
l.next = ListNode(val)
l = l.next
return head.next
