LeetCode——Merge Two Sorted Lists

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

原题链接：https://oj.leetcode.com/problems/merge-two-sorted-lists/

题目：归并两个有序链表，返回一个新的有序链表。

思路：同归并数组的解法一样，依次比较首位元素。

public ListNode mergeTwoLists(ListNode l1, ListNode l2) {ListNode p1 = l1, p2 = l2, dummy = new ListNode(-1), p = dummy;while (p1 != null && p2 != null) {if (p1.val <= p2.val) {p.next = p1;p1 = p1.next;} else {p.next = p2;p2 = p2.next;}p = p.next;}if (p1 != null)p.next = p1;if (p2 != null)p.next = p2;return dummy.next;}