Delete middle node from linked list in c

C program for Delete middle node from linked list. Here problem description and explanation.

/*
    C program for
    Delete middle node of linked list
*/
#include <stdio.h>
#include <stdlib.h>

// Linked List LinkNode
struct LinkNode
{
    int data;
    struct LinkNode *next;
};
// Singly linked list 
struct SingleLL
{
    struct LinkNode *head;
};
// Returns the new linked list
struct SingleLL *newLinkedList()
{
    // Create memory of head and tail Nodes
    struct SingleLL *sll = (struct SingleLL *)
    malloc(sizeof(struct SingleLL));
    if (sll == NULL)
    {
        printf("Memory overflow\n");
    }
    else
    {
        sll->head = NULL;
    }
    return sll;
}
// Handles the request of adding new node at beginning of linked list
void addNode(struct SingleLL *sll, int data)
{
    // Create dynamic node
    struct LinkNode *node = (struct LinkNode *)
    malloc(sizeof(struct LinkNode));
    if (node == NULL)
    {
        printf("Memory overflow to Create LinkNode\n");
        return;
    }
    else
    {
        // Set initial node value
        node->data = data;
        node->next = sll->head;
    }
    sll->head = node;
}
// Display linked list element
void display(struct LinkNode *node)
{
    if (node == NULL)
    {
        return;
    }
    struct LinkNode *temp = node;
    // iterating linked list elements
    while (temp != NULL)
    {
        // Display node value
        printf(" %d →", temp->data);
        // Visit to next node
        temp = temp->next;
    }
    printf(" NULL\n");
}
// Delete the middle node of linked list
void deleteMid(struct LinkNode *head)
{
    if (head == NULL)
    {
        // When linked list are no elements
        printf("\nEmpty Linked List\n");
    }
    else if (head->next == NULL && 
             head->next->next == NULL)
    {
        // When linked list are less than  of 3 nodes
        printf("\nLess then 3 node of linked list\n");
    }
    else
    {
        struct LinkNode *temp = head;
        struct LinkNode *midPrevious = NULL;
        // Find the middle and its previous node
        while (temp != NULL && 
               temp->next != NULL && 
               temp->next->next != NULL)
        {
            if (midPrevious == NULL)
            {
                // When first node
                midPrevious = temp;
            }
            else
            {
                // Visit to next node
                midPrevious = midPrevious->next;
            }
            // Visit to next second next node
            temp = temp->next->next;
        }
        // Get the node which is deleting 
        temp = midPrevious->next;
        // Show deleted node
        printf("Delete node : %d\n", temp->data);
        // Change link
        midPrevious->next = temp->next;
        free(temp);
    }
}
int main(int argc, char
    const *argv[])
{
    struct SingleLL *sll = newLinkedList();
    // Linked list
    // 7 → 6 → 5 → 4 → 3 → 2 → 1 → NULL
    addNode(sll,1);
    addNode(sll,2);
    addNode(sll,3);
    addNode(sll,4);
    addNode(sll,5);
    addNode(sll,6);
    addNode(sll,7);
    printf(" Linked List \n");
    display(sll->head);
    printf("Before Delete middle node\n");
    display(sll->head);
  
    deleteMid(sll->head);
    printf("After Delete middle node\n");
    display(sll->head);
    return 0;
}

Output

 Linked List
 7 → 6 → 5 → 4 → 3 → 2 → 1 → NULL
Before Delete middle node
 7 → 6 → 5 → 4 → 3 → 2 → 1 → NULL
Delete node : 4
After Delete middle node
 7 → 6 → 5 → 3 → 2 → 1 → NULL



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