添加两个数字 - Python - Leetcode - AttributeError: 'ListNode' object 没有属性 'reverse'

Question

I'm trying to solve this problem on [LeetCode] https://leetcode.com/problems/add-two-numbers/

When I copy my code into PyCharm it works correctly. However when I submit it too LeetCode I receive this error:

AttributeError: 'ListNode' object has no attribute 'reverse' l1.reverse()

Can someone check if my code is incorrect, or if the issue is something to do with LeetCode's IDE?

Here is my code:

# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution(object):
    def addTwoNumbers(self, l1, l2):
        """
        :type l1: ListNode
        :type l2: ListNode
        :rtype: ListNode
        """
        l1.reverse()
        l2.reverse()

        s1 = [str(x) for x in l1]
        res1 = int("".join(s1))
    
        s2 = [str(x) for x in l2]
        res2 = int("".join(s2))

        ans = res1 + res2

        ans1 = [int(x) for x in str(ans)]

        ans1.reverse()
        
        return(ans1)

I adjusted the code somewhat for PyCharm, but this is the code that actually works:

l1 = [4,5,6]
l2 = [6,2,3]

l1.reverse()
l2.reverse()

s1 = [str(x) for x in l1]
res1 = int("".join(s1))

s2 = [str(x) for x in l2]
res2 = int("".join(s2))

ans = res1 + res2

ans1 = [int(x) for x in str(ans)]

ans1.reverse()
print(ans1)

Answer 1

The arguments passed by Leetcode are ListNode type and not default list, so you have to write your own reverse method. In pycharm your inputting arguments of type list, which has a reverse method, and thats why ur code is working on pycharm.