题解 | #链表中的节点每k个一组翻转#
链表中的节点每k个一组翻转
https://www.nowcoder.com/practice/b49c3dc907814e9bbfa8437c251b028e
import java.util.*; /* * public class ListNode { * int val; * ListNode next = null; * } */ public class Solution { /** * * @param head ListNode类 * @param k int整型 * @return ListNode类 */ public ListNode reverseKGroup (ListNode head, int k) { // write code here if(head == null) return head; List<ListNode> list=new ArrayList<>(); ListNode curr=head; while(curr != null){ list.add(curr); curr=curr.next; } for(int i=0;i+k<=list.size();i+=k){ for(int j=i;j<i+k/2;j++){ ListNode temp=list.get(j); list.set(j,list.get(k+2*i-1-j)); list.set(k+2*i-1-j,temp); } } for(int i=0;i<list.size()-1;i++){ list.get(i).next=list.get(i+1); } list.get(list.size()-1).next=null; return list.get(0); } }