题解 | #链表内指定区间反转#

利用栈stack把链表数据置换

import java.util.*;
/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 * }
 */
public class Solution {
    /**
     *
     * @param head ListNode类
     * @param m int整型
     * @param n int整型
     * @return ListNode类
     */
    public ListNode reverseBetween (ListNode head, int m, int n) {
        Stack stack = new Stack();
        ListNode temp = null;
        ListNode p = head;
        int size = 0;
        while (head != null) {
            size++;
            if (size >= m && size <= n) {
                stack.push(head.val);      
            }
            head = head.next;
        }
        head = p;
        size = 0;
        while (head != null) {
            size++;
            if (size >= m && size <= n) {
                head.val = stack.pop();
            }
            head = head.next;
        }
        return p;
    }
}