import java.util.*;

/*

  • public class ListNode {
  • int val;
  • ListNode next = null;
  • public ListNode(int val) {
  • this.val = val;
    
  • }
  • } */

public class Solution { /** * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可 * * * @param head ListNode类 * @return ListNode类 */ public ListNode oddEvenList (ListNode head) { // write code here if (head == null) { return head; } ListNode evenHead = head.next; ListNode odd = head, even = evenHead; while (even != null && even.next != null) { odd.next = even.next; odd = odd.next; even.next = odd.next; even = even.next; } odd.next = evenHead; return head; } }