LeetCode题解 2.Add Two Numbers (两数相加)


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


【LeetCode题解 2.Add Two Numbers (两数相加)】迭代解法
/** * Definition for singly-linked list. * public class ListNode { *int val; *ListNode next; *ListNode(int x) { val = x; } * } */ public class Solution { public ListNode addTwoNumbers(ListNode l1, ListNode l2) { ListNode dummyHead = new ListNode(0); if(l1 == null && l2 == null){ return dummyHead; } int sum = 0, carry = 0; ListNode curr = dummyHead; while(l1!=null || l2!=null){ int num1 = l1 == null? 0 : l1.val; int num2 = l2 == null? 0 : l2.val; sum = num1 + num2 + carry; curr.next = new ListNode(sum % 10); curr = curr.next; carry = sum / 10; l1 = l1 == null? null : l1.next; l2 = l2 == null? null : l2.next; } if(carry!=0){ curr.next = new ListNode(carry); } return dummyHead.next; } }


    推荐阅读