C Programming Code Examples

C > Linked Lists Code Examples

Search for an Element in the Linked List without using Recursion

Search for an Element in the Linked List without using Recursion

This C program, using iteration, searches for an element in a linked list. A linked list is an ordered set of data elements, each containing a link to its successor.

    #include <stdio.h>

    #include <stdlib.h>

    struct node

    {

        int a;

        struct node *next;

    };

    void generate(struct node **, int);

    void search(struct node *, int);

    void delete(struct node **);

    int main()

    {

        struct node *head = NULL;

        int key, number;

        printf("Enter the number of nodes: ");

        scanf("%d", &number);

        printf("\nDisplaying the list\n");

        generate(&head, number);

        printf("\nEnter key to search: ");

        scanf("%d", &key);

        search(head, key);

        delete(&head);

        return 0;

    }

    void generate(struct node **head, int number)

    {

        int i;

        struct node *temp;

        for (i = 0; i < number; i++)

        {

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

            temp->a = rand() % number;

            if (*head == NULL)

            {

                *head = temp;

                temp->next = NULL;

            }

            else

            {

                temp->next = *head;

                *head = temp;

            }

            printf("%d  ", temp->a);

        }

    }

    void search(struct node *head, int key)

    {

        while (head != NULL)

        {

            if (head->a == key)

            {

                printf("key found\n");

                return;

            }

            head = head->next;

        }

        printf("Key not found\n");

    }

    void delete(struct node **head)

    {

        struct node *temp;

        while (*head != NULL)

        {

            temp = *head;

            *head = (*head)->next;

            free(temp);

        }

    }