// C++ program to delete middle
// of a linked list
#include 
using namespace std;

/* Link list Node */
struct Node {
int data;
struct Node* next;
};
// count of nodes
int countOfNodes(struct Node* head)
{
int count = 0;
while (head != NULL) {
head = head->next;
count++;
}
return count;
}

// Deletes middle node and returns
// head of the modified list
struct Node* deleteMid(struct Node* head)
{
// Base cases
if (head == NULL)
return NULL;
if (head->next == NULL) {
delete head;
return NULL;
}
struct Node* copyHead = head;

// Find the count of nodes
int count = countOfNodes(head);

// Find the middle node
int mid = count / 2;

// Delete the middle node
while (mid-- > 1) {
head = head->next;
}

// Delete the middle node
head->next = head->next->next;

return copyHead;
}

// A utility function to print
// a given linked list
void printList(struct Node* ptr)
{
while (ptr != NULL) {
cout << ptr->data << "->";
ptr = ptr->next;
}
cout << "NULL\n";
}

// Utility function to create a new node.
Node* newNode(int data)
{
struct Node* temp = new Node;
temp->data = data;
temp->next = NULL;
return temp;
}

/* Driver program to test above function*/
int main()
{
/* Start with the empty list */
struct Node* head = newNode(1);
head->next = newNode(2);
head->next->next = newNode(3);
head->next->next->next = newNode(4);

cout << "Given Linked List\n";
printList(head);

head = deleteMid(head);

cout << "Linked List after deletion of middle\n";
printList(head);

return 0;
}