LeetCode Palindrome Linked List

Description

Given a singly linked list, determine if it is a palindrome.

The original problem is here.

The original code is here.

My Solution

I solve this problem in C++, as below:

/*
*Palindrome Linked List   
*Author: shuaijiang
*Email: zhaoshuaijiang8@gmail.com
*/
#include<iostream>
#include<stdlib.h>
using namespace std;

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
 
 struct ListNode {
    int val;
    ListNode *next;
    ListNode(int x) : val(x), next(NULL) {}
 };
class Solution {
public:
    bool isPalindrome(ListNode* head) {
        if(head == NULL) 
            return true;
        ListNode *list1 = head;
        ListNode *list2 = new ListNode(head->val);
        
        list2->next = NULL;
        list1 = list1->next;
        while(list1 != NULL){
            int num = list1->val;
            ListNode *node = new ListNode(num);
            node->next = list2;
            list2 = node;
            list1 = list1->next;
        }
        list1 = head;
        while(list1 != NULL && list2->next != NULL){
            if(list1->val != list2->val)
                return false;
            list1 = list1->next;
            list2 = list2->next;
        }
        return true;
    }
};
//The code under below is used for test
int main(){
    ListNode * head = new ListNode(1);
    ListNode * node1 = new ListNode(2);
    ListNode * node2 = new ListNode(0);
    head->next = node1;
    node1->next = node2;
    
    Solution s;
    bool isP = s.isPalindrome(head);
    cout<<"isP="<<isP<<endl;
    system("pause");
    return 0;
    
}

Note

To solve the problem, I first get the reverse linked list, and then compare whether the two lists is equal or not.