Datawhale编程实践（LeetCode 腾讯精选练习50）Task1

1.两数相加

https://leetcode-cn.com/problems/add-two-numbers/

自己的代码能力果然很差，写出来直接超时。

# 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_val = 0
        l1_len = 0
        while(l1.next != None):
            l1_val += l1.val * (10 ** l1_len)
            l1_len += 1

        l2_val = 0
        l2_len = 0
        while(l2.next != None):
            l2_val += l2.val * (10 ** l2_len)
            l2_len += 1
        
        res_list = []
        res_last_val = 0
        res_val = l1_val + l2_val
        res_len = max(l1_len, l2_len)
        for i in range(1, res_len+1):
            res_list.append(ListNode((res_val-res_last_val)//(10**(res_len-i))))
            res_last_val = (res_val-res_last_val)//(10**(res_len-i)) * (10**(res_len-i))
        
        for i in range(res_len-1):
            res_list[i].next = res_list[i+1]
        
        res = res_list[0]
        return res

看了官方代码和大神答案，感觉自己还得好好研究研究

2.