---
tags: leetcode
---

# [876. Middle of the Linked List](https://leetcode.com/problems/middle-of-the-linked-list/)
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# My Solution
## The Key Idea for Solving This Coding Question
## C++ Code

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */

class Solution {
public:
    ListNode *middleNode(ListNode *head) {
        ListNode *slow = head, *fast = head;
        while (fast != nullptr && fast->next != nullptr) {
            slow = slow->next;
            fast = fast->next->next;
        }

        return slow;
    }
};

## Time Complexity
$O(n)$
$n$ is the number of nodes in the linked list referred by `head`.
## Space Complexity
$O(1)$
# Miscellaneous
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