Leetcode - Palindrome Linked List

https://leetcode.com/problems/palindrome-linked-list/

Input: 1->2
Output: false

Input: 1->2->2->1
Output: true

/**
 * Definition for singly-linked list.
 * type ListNode struct {
 *     Val int
 *     Next *ListNode
 * }
 */
func isPalindrome(head *ListNode) bool {
    fast := head
    slow := head
    count := 0
    for fast != nil {
        fast = fast.Next
        count++
        if fast == nil {
            break
        }
        count++
        fast = fast.Next
        slow = slow.Next
    }
    node := head
    var prev *ListNode
    for node != slow {
        tmp := node.Next
        node.Next = prev
        prev = node
        node = tmp
    }
    node1 := prev
    node2 := slow
    if count % 2 == 1 {
        node2 = node2.Next
    }
    
    for node1 != nil && node2 != nil {
        if node1.Val != node2.Val {
            return false
        }
        node1 = node1.Next
        node2 = node2.Next
    }
    if node1 != nil || node2 != nil {
        return false
    }
    return true
}

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