445. 两数相加 II

解法1

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution:
    def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
        n1 = 0
        n2 = 0

        def make_list_node(in_list):
            now_list_node = ListNode(in_list[0])
            head = now_list_node
            if len(in_list) == 1:
                return now_list_node
            for i in range(1,len(in_list)):
                list_node = ListNode(in_list[i])
                now_list_node.next = list_node
                now_list_node = list_node
            return head

        while l1:
            n1 *= 10
            n1 += l1.val
            l1 = l1.next
            if not l1:
                break
        while l2:
            n2 *=10
            n2 += l2.val
            l2 = l2.next
            if not l2:
                break

        n = n1 + n2      

        return make_list_node( list(map(int, list(str(n)))) )

解法2

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution:
    def addTwoNumbers(self, l1: ListNode, l2: ListNode) -> ListNode:
        n1 = []
        n2 = []
        while l1:
            n1.append(l1.val)
            l1 = l1.next
            if not l1:
                break
        while l2:
            n2.append(l2.val)
            l2 = l2.next
            if not l2:
                break
        now_list_node = None

        in_flag = 0

        if min(len(n1),len(n2)) >= 1:
            t1 = n1.pop()
            t2 = n2.pop()
            print(t1,t2)
            t = t1+t2+in_flag
            in_flag = 0
            if t>=10:
                t = t-10
                in_flag = 1
            now_list_node = ListNode(t)

        for i in range(0,max(len(n1),len(n2))):
            t1 = n1.pop() if n1 else 0
            t2 = n2.pop() if n2 else 0
            print(t1,t2)
            t = t1+t2+in_flag
            in_flag = 0
            if t>=10:
                t = t-10
                in_flag = 1
    #         print(t0)
            new_list_node = ListNode(t)
            new_list_node.next = now_list_node
            now_list_node = new_list_node

        if len(n1)==0 and len(n2) == 0 and in_flag == 1:
            new_list_node = ListNode(in_flag)
            new_list_node.next = now_list_node
            now_list_node = new_list_node

        return now_list_node