两数相加python

输入： l1 = [2,4,3], l2 = [5,6,4]
输出： [7,0,8]
解释： 342 + 465 = 807.

class ListNode:
    def __init__(self,val,next):
        self.val=val
        self.next=next
        
class Solution:
   def addtwo(self,p1:ListNode,p2:ListNode):
       dummy=p=ListNode(None)
       s=0
       while p1 or p2 or s!=0:
           s+=p1.val+p2.val
           
           p.next=ListNode(s%10)
           p=p.next
           
           if p1:p1=p1.next
           if p2:p2=p2.next
           
           s//=10
       return dummy.next