数字相加

两个数字用链表存储，给定两个非空链表来表示两个非负整数。位数按照逆序方式存储，它们的每个节点只存储单个数字。将两数相加返回一个新的链表。

你可以假设除了数字 0 之外，这两个数字都不会以零开头。

示例:

输入：(2 -> 4 -> 3) + (5 -> 6 -> 4)
输出：7 -> 0 -> 8
原因：342 + 465 = 807

这个是leetcode上面的真题

代码实现如下:

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

class Solution:
    def addTwoNumbers(self, l1, l2):
        """
        :type l1: ListNode
        :type l2: ListNode
        :rtype: ListNode
        """
        l3 = ListNode(0)
        tmp1 = l1
        tmp2 = l2
        tmp3 = l3
        pre_tmp3 = l3
        while(tmp1!=None or tmp2!=None):
            if(tmp1!=None and tmp2!=None):
                tmp3.val = tmp1.val + tmp2.val +tmp3.val
                tmp1 = tmp1.next
                tmp2 = tmp2.next
            elif(tmp1!=None):
                tmp3.val = tmp1.val +tmp3.val
                tmp1 = tmp1.next
            else:
                tmp3.val = tmp2.val +tmp3.val
                tmp2 = tmp2.next

            if(tmp3.val>=10):
                tmp3.val=tmp3.val-10;
                tmp3.next = ListNode(1)
            else:
                tmp3.next = ListNode(0)
            pre_tmp3 = tmp3
            tmp3 = tmp3.next
        if(tmp3.val==0):
            pre_tmp3.next = None
        return l3
    def showNumbers(self, l1):
        while(l1 != None):
            print(l1.val, end=" ")
            l1 = l1.next
        print("")
        return
    def ListNodeList(self, *args):
        l = ListNode(0)
        tmp = l
        size = len(args)
        for i in range(size-1):
            tmp.val = args[i]
            tmp.next = ListNode(0)
            tmp = tmp.next
        tmp.val = args[size-1]

        return l


if __name__ == '__main__':
    s = Solution()
    l1 = s.ListNodeList(2, 4, 3)
    s.showNumbers(l1)
    l2 = s.ListNodeList(5, 6, 4)
    s.showNumbers(l2)
    l3 = s.addTwoNumbers(l1, l2)
    s.showNumbers(l3)
    l4 = s.addTwoNumbers(l2, l3)
    s.showNumbers(l4)

在完成代码之后对计算结果输出进行简单验证。