A complete working C program to delete a node in a linked list at a given position

#include <stdio.h>

#include <stdlib.h>

 

// A linked list node

struct node

{

    int data;

    struct node *next;

};

 

/* Given a reference (pointer to pointer) to the head of a list

   and an int, inserts a new node on the front of the list. */

void push(struct node** head_ref, int new_data)

{

    struct node* new_node = (struct node*) malloc(sizeof(struct node));

    new_node->data  = new_data;

    new_node->next = (*head_ref);

    (*head_ref)    = new_node;

}

 

/* Given a reference (pointer to pointer) to the head of a list

   and a position, deletes the node at the given position */

void deleteNode(struct node **head_ref, int position)

{

   // If linked list is empty

   if (*head_ref == NULL)

      return;

 

   // Store head node

   struct node* temp = *head_ref;

 

    // If head needs to be removed

    if (position == 0)

    {

        *head_ref = temp->next;   // Change head

        free(temp);               // free old head

        return;

    }

 

    // Find previous node of the node to be deleted

    for (int i=0; temp!=NULL && i<position-1; i++)

         temp = temp->next;

 

    // If position is more than number of ndoes

    if (temp == NULL || temp->next == NULL)

         return;

 

    // Node temp->next is the node to be deleted

    // Store pointer to the next of node to be deleted

    struct node *next = temp->next->next;

 

    // Unlink the node from linked list

    free(temp->next);  // Free memory

 

    temp->next = next;  // Unlink the deleted node from list

}

 

// This function prints contents of linked list starting from

// the given node

void printList(struct node *node)

{

    while (node != NULL)

    {

        printf(" %d ", node->data);

        node = node->next;

    }

}

 

/* Drier program to test above functions*/

int main()

{

    /* Start with the empty list */

    struct node* head = NULL;

 

    push(&head, 7);

    push(&head, 1);

    push(&head, 3);

    push(&head, 2);

    push(&head, 8);

 

    puts("Created Linked List: ");

    printList(head);

    deleteNode(&head, 4);

    puts("\nLinked List after Deletion at position 4: ");

    printList(head);

    return 0;

}

 

 Output:

Created Linked List: 
 8  2  3  1  7 
Linked List after Deletion at position 4: 
 8  2  3  1