'''
You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.

Follow up:
What if you cannot modify the input lists? In other words, reversing the lists is not allowed.

Example:

Input: (7 -> 2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 8 -> 0 -> 7
'''

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:
    def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
        str1=''
        str2=''
        while l1:
            str1+=str(l1.val)
            l1=l1.next
        while l2:
            str2+=str(l2.val)
            l2=l2.next
        ans=str(int(str1)+int(str2))
        def lst2link(lst):
            cur = dummy = ListNode(0)
            for e in lst:
                cur.next = ListNode(e)
                cur = cur.next
            return dummy.next
        return lst2link(ans)
     
        
b4d4aed951260d3f4845a6d7af68b47b769e0aae
<mask token>

<mask token>


class Solution:
    <mask token>

<mask token>


class Solution:

    def addTwoNumbers(self, l1: ListNode, l2: ListNode) ->ListNode:
        str1 = ''
        str2 = ''
        while l1:
            str1 += str(l1.val)
            l1 = l1.next
        while l2:
            str2 += str(l2.val)
            l2 = l2.next
        ans = str(int(str1) + int(str2))

        def lst2link(lst):
            cur = dummy = ListNode(0)
            for e in lst:
                cur.next = ListNode(e)
                cur = cur.next
            return dummy.next
        return lst2link(ans)

'''
You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.

Follow up:
What if you cannot modify the input lists? In other words, reversing the lists is not allowed.

Example:

Input: (7 -> 2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 8 -> 0 -> 7
'''

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:
    def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
        str1=''
        str2=''
        while l1:
            str1+=str(l1.val)
            l1=l1.next
        while l2:
            str2+=str(l2.val)
            l2=l2.next
        ans=str(int(str1)+int(str2))
        def lst2link(lst):
            cur = dummy = ListNode(0)
            for e in lst:
                cur.next = ListNode(e)
                cur = cur.next
            return dummy.next
        return lst2link(ans)
     
        