题解 | #合并两个排序的链表#

/*
public class ListNode {
    int val;
    ListNode next = null;

    ListNode(int val) {
        this.val = val;
    }
}*/
public class Solution {
    public ListNode Merge(ListNode list1, ListNode list2) {
        ListNode newHead = new ListNode(-1);
        ListNode node = newHead;
        while (list1 != null && list2 != null) {
            if (list1.val < list2.val) {
                node.next = list1;
                list1 = list1.next;
            } else {
                node.next = list2;
                list2 = list2.next;
            }
            node = node.next;
        }
        if (list1 != null) {
            node.next = list1;
        }
        if (list2 != null) {
            node.next = list2;
        }
        return newHead.next;
    }
}