**Central Linked List - Amazon Top Interview Questions**

### Problem Statement :

Given a singly linked list node, return the value of the middle node. If there's two middle nodes, then return the second one. Bonus: Solve using \mathcal{O}(1)O(1) space. Constraints n ≤ 100,000 where n is the number of nodes in node Example 1 Input node = [0, 1, 2] Output 1

### Solution :

` ````
Solution in C++ :
int solve(LLNode* node) {
LLNode *fast = node, *slow = node;
while (fast != NULL && fast->next != NULL) {
slow = slow->next;
fast = fast->next->next;
}
return slow->val;
}
```

` ````
Solution in Java :
import java.util.*;
/**
* class LLNode {
* int val;
* LLNode next;
* }
*/
class Solution {
public int solve(LLNode node) {
LLNode slow = node;
LLNode fast = node;
while (fast != null && fast.next != null) {
slow = slow.next;
fast = fast.next.next;
}
return slow.val;
}
}
```

` ````
Solution in Python :
class Solution:
def solve(self, node):
slow = node
fast = node
while fast != None and fast.next != None:
slow = slow.next
fast = fast.next.next
return slow.val
```

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