#include <stdio.h>
#include <stdlib.h>
typedef struct node *nodepointer;
typedef struct node {
nodepointer llink;
int data;
nodepointer rlink;
} Node;
void dinsert(nodepointer node, nodepointer newnode) {
newnode->llink = node;
newnode->rlink = node->rlink;
if (node->rlink != NULL)
node->rlink->llink = newnode;
node->rlink = newnode;
}
void delete(nodepointer deleted) {
if (deleted->llink != NULL)
deleted->llink->rlink = deleted->rlink;
if (deleted->rlink != NULL)
deleted->rlink->llink = deleted->llink;
free(deleted);
}
void display(nodepointer header) {
nodepointer current = header->rlink;
if (current == NULL) {
printf("List is empty\n");
return;
}
printf("List: ");
while (current != NULL) {
printf("%d ", current->data);
current = current->rlink;
}
printf("\n");
}
int main(void) {
nodepointer header = (nodepointer)malloc(sizeof(Node));
header->llink = header->rlink = NULL;
int choice;
int item;
while (1) {
printf("Enter\n 1. Insert\n 2. Delete\n 3. Display\n 4. Exit\n");
scanf("%d", &choice);
switch (choice) {
case 1:
printf("Enter data to be inserted: ");
scanf("%d", &item);
nodepointer newnode = (nodepointer)malloc(sizeof(Node));
newnode->data = item;
dinsert(header, newnode);
break;
case 2:
if (header->rlink == NULL) {
printf("List is empty. Cannot delete.\n");
break;
}
printf("Enter data to be deleted: ");
scanf("%d", &item);
nodepointer current = header->rlink;
while (current != NULL && current->data != item) {
current = current->rlink;
}
if (current == NULL) {
printf("Element not found in the list\n");
} else {
delete(current);
printf("Element deleted: %d\n", item);
}
break;
case 3:
display(header);
break;
case 4:
free(header);
exit(0);
default:
printf("Invalid choice\n");
}
}
return 0;
}