Delete the first element

Deleting the first node of the linked list. For this, the next pointer of the last will point to the second node of the linked list.

Below is the implementation of the above operation:

C

// C program for the above operation
#include <stdio.h>
#include <stdlib.h>
 
// Structure of a linked list node
struct node {
    int info;
    struct node* next;
};
 
// Pointer to last node in list
struct node* last = NULL;
 
// Function to add a new node
// at the end of the list
void addatlast(int data)
{
    // Initialize a new node
    struct node* temp;
    temp = (struct node*)malloc(sizeof(struct node));
 
    // If the new node is the only
    // node in the list
    if (last == NULL) {
        temp->info = data;
        temp->next = temp;
        last = temp;
    }
 
    // Else the new node will be the
    // last node and will contain
    // the reference of head node
    else {
        temp->info = data;
        temp->next = last->next;
        last->next = temp;
        last = temp;
    }
}
 
// Function to delete the first
// element of the list
void deletefirst()
{
    struct node* temp;
 
    // If list is empty
    if (last == NULL)
        printf("\nList is empty.\n");
 
    // Else last node now contains
    // reference of the second node
    // in the list because the
    // list is circular
    else {
        temp = last->next;
        last->next = temp->next;
        free(temp);
    }
}
 
// Function to print the list
void viewList()
{
    // If list is empty
    if (last == NULL)
        printf("\nList is empty\n");
 
    // Else print the list
    else {
        struct node* temp;
        temp = last->next;
        do {
            printf("\nData = %d", temp->info);
            temp = temp->next;
        } while (temp != last->next);
    }
}
 
// Driver Code
int main()
{
    // Initialize the list
    addatlast(10);
    addatlast(20);
    addatlast(30);
   
    printf("Before deletion:\n");
    viewList();
 
    // Function Call
    deletefirst();
 
    // Print list
    printf("\n\nAfter deletion:\n");
    viewList();
 
    return 0;
}

Output

Before deletion:

Data = 10
Data = 20
Data = 30

After deletion:

Data = 20
Data = 30

Program for all operations on Circular Linked List in C

In a Circular linked list, every element has a link to its next element in the sequence, and the last element has a link to the first element. A circular linked list is similar to the singly linked list except that the last node points to the first node. Below is the image to illustrate the same:

Delete the first element

C

Program for all operations on Circular Linked List in C

Categories

Contact US

Delete the first element

C

Program for all operations on Circular Linked List in C

Similar Reads

Categories

Contact US