UGC NET CS 2016 July - III Question 44

Introduction

The UGC NET CS 2016 July - III Question 44 is a question from the Computer Science subject. It asks about the implementation of a linked list in a programming language.

Linked List in a Programming Language

A linked list is a data structure consisting of a sequence of nodes, each containing a value and a pointer to the next node in the sequence. It is used to represent sequences or lists of items, where the order of the items is important and needs to be maintained.

To implement a linked list in a programming language, we need to define a node structure and a set of functions for creating, inserting, deleting, and traversing nodes in the list.

Node Structure

The node structure contains two fields: the data field to store the value of the node and the next field to store the pointer to the next node in the list. In C, the node structure can be defined as follows:

struct Node {
    int data;
    struct Node* next;
};

Creating a Node

To create a new node, we need to allocate memory for it using the malloc function or any other memory allocation function in the programming language. Then, we need to initialize the data and next fields of the node. Here is an example function to create a node in C:

struct Node* newNode(int data) {
    struct Node* node = (struct Node*) malloc(sizeof(struct Node));
    node->data = data;
    node->next = NULL;
    return node;
}

Inserting a Node

To insert a new node in the list, we need to find the position where we want to insert the node and modify the next pointer of the previous node to point to the new node, and the next pointer of the new node to point to the next node in the list. Here is an example function to insert a node at the beginning of the list in C:

void insertAtBeginning(struct Node** head, int data) {
    struct Node* node = newNode(data);
    node->next = *head;
    *head = node;
}

Deleting a Node

To delete a node from the list, we need to find the position where the node is located, modify the next pointer of the previous node to point to the next node after the node to be deleted, and free the memory of the node. Here is an example function to delete a node from the beginning of the list in C:

void deleteFromBeginning(struct Node** head) {
    struct Node* node = *head;
    *head = node->next;
    free(node);
}

Traversing the List

To traverse the list, we need to start from the head node and follow the next pointer of each node until we reach the end of the list. Here is an example function to print all the nodes in the list in C:

void printList(struct Node* head) {
    struct Node* node = head;
    while (node != NULL) {
        printf("%d ", node->data);
        node = node->next;
    }
    printf("\n");
}

Conclusion

In conclusion, the implementation of a linked list in a programming language requires the definition of a node structure and a set of functions for creating, inserting, deleting, and traversing nodes in the list. The code snippets in this article demonstrate the implementation of a linked list in C.