NowCoder
题目描述
解题思路
递归
代码语言：javascript复制/*
public class ListNode {
int val;
ListNode next = null;
ListNode(int val) {
this.val = val;
}
}*/
public class Solution {
public ListNode Merge(ListNode list1,ListNode list2) {
if(list1 == null)
return list2;
if(list2 == null)
return list1;
if(list1.val <= list2.val) {
list1.next = Merge(list1.next, list2);
return list1;
}else {
list2.next = Merge(list1, list2.next);
return list2;
}
}
}迭代
代码语言：javascript复制/*
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 head = new ListNode(-1);
ListNode cur = head;
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;
}
if(list1 != null)
cur.next = list1;
if(list2 != null)
cur.next = list2;
return head.next;
}
}
