C#
\npublic ListNode MiddleNode(ListNode head) {\n\tvar fast = head;\n\tvar slow = head;\n\n\twhile (fast?.next != null) {\n\t\tslow = slow.next;\n\t\tfast = fast.
```\npublic ListNode MiddleNode(ListNode head) {\n\tvar fast = head;\n\tvar slow = head;\n\n\twhile (fast?.next != null) {\n\t\tslow = slow.next;\n\t\tfast = fast.next.next;\n\t}\n\n\treturn slow;\n}\n```
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