Middle_of_linked_list.cpp

/*
Following is the class structure of the Node class:

class Node
{
public:
    int data;
    Node *next;
    Node()
    {
        this->data = 0;
        next = NULL;
    }
    Node(int data)
    {
        this->data = data;
        this->next = NULL;
    }
    Node(int data, Node* next)
    {
        this->data = data;
        this->next = next;
    }
};
*/

Node *findMiddle(Node *head)
{
    // Write your code here
    if (head->next == NULL)
        return head;
    Node *slow = head;       // move only one step
    Node *fast = head->next; // move two steps
    while (fast->next != NULL && fast->next->next != NULL)
    {
        slow = slow->next;
        fast = fast->next->next;
    }
    return slow->next;
}