"""

876. Middle of the Linked List
Easy

901

49

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Given a non-empty, singly linked list with head node head, return a middle node of linked list.

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

 

Example 1:

Input: [1,2,3,4,5]
Output: Node 3 from this list (Serialization: [3,4,5])
The returned node has value 3.  (The judge's serialization of this node is [3,4,5]).
Note that we returned a ListNode object ans, such that:
ans.val = 3, ans.next.val = 4, ans.next.next.val = 5, and ans.next.next.next = NULL.
Example 2:

Input: [1,2,3,4,5,6]
Output: Node 4 from this list (Serialization: [4,5,6])
Since the list has two middle nodes with values 3 and 4, we return the second one.
 

Note:

The number of nodes in the given list will be between 1 and 100.

"""
class ListNode:
    def __init__(self, x):
        self.val = x
        self.next = None


    def middleNode(self, head: ListNode) -> ListNode:
        result = [head]
        while result[-1].next:
            result.append(result[-1].next)
        return result[len(result)// 2]


    def middleNode2(self, head: ListNode) -> ListNode:
        pointer1 = head
        pointer2 = head
        while pointer2 and pointer2.next:
            pointer1 = pointer1.next
            pointer2 = pointer2.next.next
        return pointer1