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Middle of the Linked List

Problem statement​

Given the head of a singly linked list, return the middle node of the linked list.

If there are two middle nodes, return the second middle node.

Example 1:

Input: head = [1,2,3,4,5]Output: [3,4,5]Explanation: The middle node of the list is node 3.

Example 2:

Input: head = [1,2,3,4,5,6]Output: [4,5,6]Explanation: Since the list has two middle nodes with values 3 and 4, we return the second one.

Constraints:

  • The number of nodes in the list is in the range [1, 100].
  • 1 <= Node.val <= 100

My solution​

/**
 * Definition for singly-linked list.
 * function ListNode(val, next) {
 *     this.val = (val===undefined ? 0 : val)
 *     this.next = (next===undefined ? null : next)
 * }
 */
/**
 * @param {ListNode} head
 * @return {ListNode}
 */
var middleNode = function(head) {
    let count = 0;
    let node = head;
    
    while (node) {
        count++;
        node = node.next;
    }
    
    const middle = Math.floor(count/2);
    
    node = head;
    count = 0;
    
    while (node) {
        if (count === middle) {
            break
        }
        count++;
        node = node.next;
    }
    
    return node;
};