From 65901bdee41eb6071ca6c03209b114bcf562ffd4 Mon Sep 17 00:00:00 2001
From: jerryfishcode <91447694+jerryfishcode@users.noreply.github.com>
Date: Mon, 27 Sep 2021 21:07:45 +0800
Subject: [PATCH] =?UTF-8?q?=E5=A2=9E=E5=8A=A0=20234.=20=E5=9B=9E=E6=96=87?=
 =?UTF-8?q?=E9=93=BE=E8=A1=A8=20JavaScript=20=E7=89=88=E6=9C=AC?=
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---
 problems/0234.回文链表.md | 36 ++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/problems/0234.回文链表.md b/problems/0234.回文链表.md
index 631d2f6b..c93e534e 100644
--- a/problems/0234.回文链表.md
+++ b/problems/0234.回文链表.md
@@ -284,7 +284,41 @@ class Solution:
 ## JavaScript
 
 ```js
-
+var isPalindrome = function(head) {
+    const reverseList = head => {// 反转链表
+        let temp = null;
+        let pre = null;
+        while(head != null){
+            temp = head.next;
+            head.next = pre;
+            pre = head;
+            head = temp;
+        }
+        return pre;
+    }
+    // 如果为空或者仅有一个节点，返回true
+    if(!head && !head.next) return true;
+    let slow = head;
+    let fast = head;
+    let pre = head;
+    while(fast != null && fast.next != null){
+        pre = slow; // 记录slow的前一个结点
+        slow = slow.next;
+        fast = fast.next.next;
+    }
+    pre.next = null; // 分割两个链表
+    // 前半部分
+    let cur1 = head;
+    // 后半部分。这里使用了反转链表
+    let cur2 = reverseList(slow);
+    while(cur1 != null){
+        if(cur1.val != cur2.val) return false;
+        // 注意要移动两个结点
+        cur1 = cur1.next;
+        cur2 = cur2.next;
+    }
+    return true;
+};
 ```