leetcode :24 题。
如果最后只有一个元素,也就是单数 忽略。
C#:
/**
* Definition for singly-linked list.
* public class ListNode {
* public int val;
* public ListNode next;
* public ListNode(int val=0, ListNode next=null) {
* this.val = val;
* this.next = next;
* }
* }
*/
public class Solution {
public ListNode SwapPairs(ListNode head) {
var dummyHead = new ListNode();
dummyHead.next = head;
var cur = dummyHead;
while(cur.next != null && cur.next.next != null)
{
var temp = cur.next;
var temp1 = cur.next.next.next;
cur.next = cur.next.next;
cur.next.next = temp;
temp.next = temp1;
cur = cur.next.next;
}
return dummyHead.next;
}
}