test 2

#include<stdio.h>
#include<stdlib.h>

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

void insert(node *pointer, int data)
{
    node *start = pointer;

    /* Iterate through the list till we encounter the last node.*/
    while (pointer->next != start)
    {
        pointer = pointer->next;
    }
    /* Allocate memory for the new node and put data in it.*/
    pointer->next = (node *) malloc(sizeof(node));
    pointer = pointer->next;
    pointer->data = data;
    pointer->next = start;
    printf("%d entered.\n", data);
}

int find(node *pointer, int key)
{
    node *start = pointer;
    pointer = pointer->next; //First node is dummy node.
    /* Iterate through the entire linked list and search for the key. */
    while (pointer != start)
    {
        if (pointer->data == key) //key is found.
        {
            return 1;
        }
        pointer = pointer->next;//Search in the next node.
    }
    /*Key is not found */
    return 0;
}

void delete(
node *pointer,
int data
)
{
node *start = pointer;
/* Go to the node for which the node next to it has to be deleted */
while(pointer->next!=
start &&(pointer
->next)->data != data)
{
pointer = pointer->next;
}
if(pointer->next==start)
{
printf("Element %d is not present in the list\n",data);
return;
}
/* Now pointer points to a node and the node next to it has to be removed */
node *temp;
temp = pointer->next;
printf("%d deleted.\n",data);
/temp points to the node which has to be removed/
pointer->
next = temp->next;
/*We removed the node which is next to the pointer (which is also temp) */
free(temp);
/* Beacuse we deleted the node, we no longer require the memory used for it .
   free() will deallocate the memory.
 */
return;
}

void print(node *start, node *pointer)
{
    if (pointer == start)
    {
        return;
    }
    printf("%d ", pointer->data);
    print(start, pointer->next);
}

int main()
{
    /* start always points to the first node of the linked list.
       temp is used to point to the last node of the linked list.*/
    node *start, *temp;
    start = (node *) malloc(sizeof(node));
    temp = start;
    temp->next = start;
    /* Here in this code, we take the first node as a dummy node.
       The first node does not contain data, but it used because to avoid handling special cases
       in insert and delete functions.
     */
    printf("1. Insert\n");
    printf("2. Delete\n");
    printf("3. Print\n");
    printf("4. Find\n");
    while (1)
    {
        int query;
        scanf("%d", &query);
        if (query == 1)
        {
            int data;
            scanf("%d", &data);
            insert(start, data);
        }
        else if (query == 2)
        {
            int data;
            scanf("%d", &data);
            delete (start, data);
        }
        else if (query == 3)
        {
            printf("The list is ");
            print(start, start->next);
            printf("\n");
        }
        else if (query == 4)
        {
            int data;
            scanf("%d", &data);
            int status = find(start, data);
            if (status)
            {
                printf("Element Found\n");
            }
            else
            {
                printf("Element Not Found\n");
            }
        }
    }
}