解题思路
首先找到链表中点，对中点及以后的链表进行反转，分别对比左右两端节点的值是否相等
参考代码
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| class Solution {
public boolean isPalindrome(ListNode head) {
ListNode mid = middleNode(head);
ListNode head2 = reverseNode(mid);
while(head2 != null) {
if(head.val != head2.val) {
return false;
}
head = head.next;
head2 = head2.next;
}
return true;
}
private ListNode middleNode(ListNode head) {
ListNode slow = head;
ListNode fast = head;
while(fast != null && fast.next != null) {
slow = slow.next;
fast = fast.next.next;
}
return slow;
}
private ListNode reverseNode(ListNode head) {
ListNode pre = null;
ListNode cur = head;
while(cur != null) {
ListNode tmp = cur.next;
cur.next = pre;
pre = cur;
cur = tmp;
}
return pre;
}
}NoL
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