21. 合并两个有序链表 - LeetCode

21. 合并两个有序链表

题目链接

迭代

class Solution {
    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
        ListNode head = new ListNode();
        ListNode p = head;
        while(l1 != null && l2 != null){
            p.next = new ListNode();
            p = p.next;
            if(l1.val < l2.val){
                p.val = l1.val;
                l1 = l1.next;
            } else{
                p.val = l2.val;
                l2 = l2.next;
            }
        }
        p.next = l1 == null? l2: l1;
        return head.next;
    }
}

• 类似合并有序数组，最后可以把l1或l2中剩下的直接接到后面