LeetCode 21. 合并两个有序链表
原题链接
简单
作者:
caichuntao
,
2023-06-28 14:16:33
,
所有人可见
,
阅读 89
方法1:迭代
时间复杂度:$O(m + n)$
空间复杂度:$O(1)$
解题思路
https://leetcode.cn/problems/merge-two-sorted-lists/solution/he-bing-liang-ge-you-xu-lian-biao-by-leetcode-solu/
Java 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 mergeTwoLists(ListNode list1, ListNode list2) {
ListNode dummy = new ListNode(-1);
ListNode pre = dummy;
while (list1 != null && list2 != null) {
if (list1.val < list2.val) {
pre.next = list1;
list1 = list1.next;
} else {
pre.next = list2;
list2 = list2.next;
}
pre = pre.next;
}
pre.next = list1 == null ? list2 : list1;
return dummy.next;
}
}