C Programming Code Examples
C > Linked Lists Code Examples
C Program to Search for an Element in the Linked List using Recursion
/* C Program to Search for an Element in the Linked List using Recursion
This C Program uses recursive function & search 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, int);
void delete(struct node **);
int main()
{
struct node *head;
int key, number;
printf("Enter the number of nodes: ");
scanf("%d", &number);
generate(&head, number);
printf("\nEnter key to search: ");
scanf("%d", &key);
search(head, key, number);
delete(&head);
}
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;
printf("%d ", temp->a);
if (*head == NULL)
{
*head = temp;
(*head)->next = NULL;
}
else
{
temp->next = *head;
*head = temp;
}
}
}
void search(struct node *head, int key, int index)
{
if (head->a == key)
{
printf("Key found at Position: %d\n", index);
}
if (head->next == NULL)
{
return;
}
search(head->next, key, index - 1);
}
void delete(struct node **head)
{
struct node *temp;
while (*head != NULL)
{
temp = *head;
*head = (*head)->next;
free(temp);
}
}
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