#include<stdio.h>
#include<stdlib.h>
typedef struct node Node;
struct node {
    int data;
    Node *next;
};

Node *create_node(int item, Node *next)
{
    Node *new_node = (Node *) malloc(sizeof(Node));
    if(new_node == NULL) {
        printf("Error! Could Not Create A New Node\n");
        exit(1);
    }
    new_node->data = item;
    new_node->next = next;
    return new_node;
}

Node *prepend(Node *head, int item)
{
    Node *new_node = create_node(item, head);
    return new_node;
}

Node *append(Node *head, int item)
{
    Node *new_node = create_node(item, NULL);
    if(head == NULL) {
        return new_node;
    }
    Node *current_node = head;
    while(current_node->next != NULL) {
        current_node = current_node->next;
    }
    current_node->next = new_node;
    return head;
}

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

int count(Node *head)
{
    int count = 0;
    Node *current_node = head;
    while(current_node != NULL) {
        count++;
        current_node = current_node->next;
    }
   return count;
}

Node *search(Node *head, int item)
{
    Node *current_node = head;
    while(current_node != NULL) {
        if(current_node->data == item)
        return current_node;
        else 
        current_node = current_node->next;
    }
    return current_node;
}

Node *remove_node(Node *head, Node *node)
{
    if (node == head) {
        head = node->next;
        free(node);
        return head;
    }
    Node *current_node = head;
    while(current_node != NULL) {
        if(current_node->next == node) {
            break;
        }
        current_node = current_node->next;
    }
    if(current_node == NULL) {
        return head;
    }
    current_node->next = node->next;
    free(node);
    return head;
}
void insert(Node *node, int item)
{
    Node *new_node = create_node(item, node->next);
    node->next = new_node;
    print_linked_list(node);

}

int main()
{
    Node *n1, *n2, *head, *n3;
    head = NULL;
    n1 = create_node(10, NULL);
    head = n1;
    print_linked_list(head);
    head = prepend(head, 20);
    print_linked_list(head);
    head = append(head, 30);
    print_linked_list(head);
    printf("Number of Node = %d\n", count(head));
    printf("Searching Node is = %d\n",(search(head, 30))->data);
    head = remove_node(head, n1);
    print_linked_list(head);
    n2 = head;
    head = remove_node(head, n2);
    print_linked_list(head);
    n2 = head;
    head = remove_node(head, n2);
    print_linked_list(head);
    insert(head, 20);
    return 0;
}