Lintcode Python Simple-level topic list summation

Description of the original title:

You have two integers that are represented by a linked list, where each node contains a number. The numbers are stored in the order of the original integers 相反 so that the first number is at the beginning of the list. Write a function that adds two integers and returns the sum in the form of a list.

Have you ever encountered this problem in a real interview? Yes Sample Example

Give two linked lists 3->1->5->null and 5->9->2->null , return8->0->8->null

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# Definition for singly-linked list.# class listnode:#     def __init__ (self, x): #         self.val = x#         Self.next = Nonec Lass Solution:    # @param l1:the first list    # @param l2:the second list    # @return: The sum list of L1 and l2
   def addlists (self, L1, L2):        # Write your code here

　　

Topic Analysis:

函数addLists，入参为两个链表，长度无限制，即可能存在长度：list1 > list2; list1 = list2; list1 < list2;

The final linked list length is based on the longest linked list length n, which returns the list length (n~n+1)

# Definition for singly-linked list.# class listnode:# def __init__ (self, x): # self.val = x# Self.next  = Noneclass Solution: # @param l1:the First list # @param l2:the second List # @return: The sum list of L1 and L2 def addlists (self, L1, L2): # Write your code here if L1 are None:return L2 if L2 is None:re Turn L1 head1 = L1 head2 = L2 flag = 0 While head1.next are not None or HEAD2.N Ext is not None: # The existence of a linked list when next is empty, constructs Next.val = 0, does not affect the addition result if Head1.next is none:head1. Next = ListNode (0) If head2.next is None:head2.next = ListNode (0) Su                Mnum = Head1.val + head2.val if sumnum >= 10:head1.val = sumnum%10 flag = 1 Head1.next.val + = 1 Else:head1.val = Sumnum flag = 0 He        AD1 = Head1.next    Head2 = Head2.next Else: # When the end of the list is processed separately, and is greater than 10 o'clock, append node Head1.val = head1.val + head2.val If head1.val >= 10:head1.val = head1.val%10 Head1.next = ListNode (1) retur n L1

　　

Lintcode Python Simple-level topic list summation