2. 两数相加
思路
新建一个链表保存结果,记录两个链表每个对应节点相加的值,并记录进位,还要判断两个链表当前操作节点是否为空
代码:
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode() {}
* ListNode(int val) { this.val = val; }
* ListNode(int val, ListNode next) { this.val = val; this.next = next; }
* }
*/
class Solution {
public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
ListNode l3=new ListNode(0);
ListNode cur=l3;
ListNode p=l1;
ListNode q=l2;
int carry=0;
while(p!=null || q!=null || carry!=0){
int x=p!=null? p.val:0;
int y=q!=null? q.val:0;
int sum=x+y+carry;
carry=sum/10;
cur.next=new ListNode(sum%10);
cur=cur.next;
p=p==null? null:p.next;
q=q==null? null:q.next;
}
return l3.next;
}
}