【题目】
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
【举例】
Example:
Input: (2 -> 4 -> 3) + (5 -> 6 -> 4) Output: 7 -> 0 -> 8 Explanation: 342 + 465 = 807.
【题目翻译】
给定两个数字链表, 然后把它们相加, 得到和链表, 具体见上面的example。
【解题思路】
其实这道题思路还是挺明显的, 无非就是同步遍历两个链表, 相加求和。
【实现代码】
# 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
"""
lead = ListNode(0)
p = lead
carry = 0
while l1 != None and l2 != None: #两个列表同步遍历, 依次相加
value = (carry+ l1.val + l2.val)%10
p.next = ListNode(value)
p = p.next
carry = (carry + l1.val + l2.val)//10
l1 = l1.next
l2 = l2.next
remain = l1 if l1 != None else l2 #把剩余的一个列表加完
while remain != None:
value = (carry + remain.val)%10
p.next = ListNode(value)
p = p.next
carry = (carry + remain.val)//10
remain = remain.next
if carry == 1: #如果列表加完以后还有进位
p.next = ListNode(1)
return lead.next