题解 | #链表内指定区间反转#

import java.util.*;
public class Solution {
    public ListNode reverseBetween (ListNode head, int m, int n) {
        // write code here
        if(head==null||head.next==null||m==n)
            return head;

        ListNode newHead = new ListNode(0);
        ListNode pre = newHead;
        pre.next = head;

        for(int i = 1 ; i < m ; i++){
            pre = pre.next;
        }
        ListNode cur = pre.next;
        for(int i = m ; i < n ;i++){
            ListNode temp = cur.next;
            cur.next = temp.next;
            temp.next = pre.next;
            pre.next = temp;
        }
        return newHead.next;
    }
}