struct mode{ int data; struct node prev; struct node next; }; struct node* head;
void append(){ int item; struct node ptr; ptr =(struct node) malloc (size of(struct node)); printf("enter node data:"); scanf("%d", & item); if(ptr == null){ printf("over low"); }else{ if(head == null){ ptr->next = null; ptr->prev =null; ptr->data = item; head = ptr; }else{ ptr->data = item; ptr->prev = null; ptr->next = head; head-> prev = ptr; head = ptr; } printf("\nNode INSERTED\n"); } } void insert at begin(){ int item; struct node ptr; ptr=(struct node)malloc(size of(struct node)); printf("enter node data:"); scanf("%d", & item); if(ptr == null){ printf("overflow"); }else{ if(head == null){ ptr->next =null; ptr->prev =null; ptr->data =item; head = ptr; }else{ ptr->data =item; ptr->prev =null; ptr->next =head; head->prev =ptr; } printf("\nNode Inserted\n"); } } int main(){ int x: while?(1){ printf("\n doubly linked list \n") printf("1. appennd \n2. display\n enter your choice:\n"); scanf("%d", & x); switch(x){ case1: append(): break; case2: traverse(); break; default: printf("\n invalid input\n") } } }