leetcode merge-two-sorted-lists

题目

将两个有序链表合并为一个新的有序链表并返回。新链表是通过拼接给定的两个链表的所有节点组成的。 

示例：

输入：1->2->4, 1->3->4
输出：1->1->2->3->4->4


解答

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
class Solution {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        ListNode newListNode = new ListNode(0);
        ListNode cur = newListNode;
        while (l1 != null && l2 != null) {
            if (l1.val < l2.val) {
                cur.next = l1;
                cur = cur.next;
                l1 = l1.next;
            }else {
                cur.next = l2;
                cur = cur.next;//指向下一个节点
                l2 = l2.next;
            }
        }
        if (l1 == null) {
            cur.next = l2;
        }else {
            cur.next = l1;
        }
        return newListNode.next;
    }
}