向后添加和迭代链表以产生向后求和

Question

I am trying to add two linked lists backward such that they produce a third. I am running into an issue in which I am missing the middle value in my expected out output. I don't understand why this is happening.

Example: 342 + 465 = 807(expected output)

input =

[2]->[4]->[3],

[5]->[6]->[4]

expected = [7]->[0]->[8]

actual = [7]->[8]

   carryOver = 0
   current1 = l1
   current2 = l2
   result = None
   resultC = None
   while current1 is not None:
       val = current1.val + current2.val+ carryOver
       if val>= 10: 
           carryOver = val//10  
       else:
           carryOver = 0 

       val = val%10  

       if result == None:
           result = ListNode(val)
           resultC = result 
       else:
           resultC.next = ListNode(val) 
       current1 = current1.next
       current2 = current2.next

   if carryOver != 0:
       resultC.next = ListNode(carryOver)

   return result

Answer 1

This might be what you are looking for.

def add_list(l1,l2):

    max_length=max(len(l1),len(l2))
    l1,l2=[[0]]*(max_length-len(l1))+l1,[[0]]*(max_length-len(l2))+l2 # padding zeros
    l1,l2=l1[::-1],l2[::-1]#temporary reversing of list
    carry=0
    d=[]
    for x in zip(l1,l2):
        tempsum=x[0][0]+x[1][0]+carry

        carry=0
        if tempsum>9:
            carry,tempsum=tempsum//10,tempsum%10
        d.append([tempsum])
    if carry !=0: 
        d.append([carry])
    return d[::-1]