【hot100-java】【合并两个有序链表】
记忆中，两个指针合并即可。
建立哨兵节点dum
/**
* 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(0),cur=dummy;
while(list1!=null && list2!=null){
if(list1.val<list2.val){
cur.next=list1;
list1=list1.next;
}
else{
cur.next=list2;
list2=list2.next;
}
cur=cur.next;
}
cur.next=list1!=null?list1:list2;
return dummy.next;
}
} 