import java.util.*; public class Solution { public ListNode reverseKGroup (ListNode head, int k) { // write code here if (head == null) return head; ListNode head1 = head; //记录链表总长度 int length = 1; while(head1.next!=null){ head1 = head1.next; length++; } // System.out.print("length="+length); head1 ...