链表之两数相加
解决方式
python
def addTwoNumbers(self, l1: Optional[ListNode], l2: Optional[ListNode]) -> Optional[ListNode]:
dummy = ListNode(0)
curr = dummy
# 进位处理
carry = 0
while l1 or l2 or carry:
sum = carry
if l1:
sum += l1.val
l1 = l1.next
if l2:
sum += l2.val
l2 = l2.next
carry = int(sum / 10)
curr.next = ListNode(int(sum % 10))
curr = curr.next
return dummy.next复杂度
时间复杂度：O(n)
空间复杂度：O(1)