# Palindrome Linked List - Amazon Top Interview Questions

### Problem Statement :

```Given a singly linked list node whose values are integers, determine whether the linked list forms a palindrome.

Constraints

n ≤ 100,000 where n is the length of node

Example 1

Input

node = [5, 3, 5]

Output

True

Explanation

5 -> 3 -> 5 is a palindrome.

Example 2

Input

node = [12, 8, 12]

Output

True

Explanation

The values of the linked list are the same forwards and backwards.```

### Solution :

```                        ```Solution in C++ :

bool checkPalindrome(LLNode *node, LLNode **curr) {
if (node == NULL) return true;
bool check = checkPalindrome(node->next, curr);
if (node->val != (*curr)->val) return false;
*curr = (*curr)->next;
return check;
}
bool solve(LLNode *node) {
LLNode *curr = node;
return checkPalindrome(node, &curr);
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, node):
fast, slow = node, node
while fast and fast.next:
fast = fast.next.next
slow = slow.next

right = None
while slow:
p = slow.next
slow.next = right
right = slow
slow = p

left = node
while left is not None and right is not None:
if left.val != right.val:
return False
left = left.next
right = right.next
return True```
```

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