doubleylinkedlist.c

#include<stdio.h>
#include <stdlib.h>
struct node{
    int data;
    struct node*next;
    struct node*prev;
};
void traverse1(struct node* head){
    struct node*p = head;
    do{
        printf("Elements %d \n" , p->data);
        p=p->next;
    }while(p != NULL);
}
void traverse2(struct node*head){
    struct node *p = head;
    while(p!= NULL && p->next != NULL){
        p=p->next;
    }
    while(p!=NULL){
        printf("Elements opposite %d\n" ,p->data );
        p=p->prev;
    }
}
struct node * reverse(struct node* head){
    struct node *current = head;
    struct node*temp = NULL;
    while (current!= NULL){
        temp = current->prev;
        current -> prev = current -> next;
        current -> next = temp;

        current = current -> prev;
    }
    if(temp != head){
        head = temp->prev;
    }
    return head;
}
int main (){
    struct node *head ;
    struct node *second;
    struct node * third; 
    struct node * fourth ;
    head = (struct node *)malloc (sizeof(struct node));
    second = (struct node*)malloc(sizeof(struct node));
    third = (struct node *)malloc(sizeof(struct node));
    fourth = (struct node*)malloc (sizeof(struct node));
    head -> data = 32;
    head -> next = second;
    head -> prev = NULL;
    second -> data = 72;
    second -> next = third;
    second -> prev = head;
    third -> data = 992;
    third -> next = fourth;
    third -> prev = second;
    fourth -> data = 320;
    fourth -> next = NULL;
    fourth -> prev = third;
    traverse1(head);
    printf(" \n");
    traverse2(head);
    printf(" \n");
    printf("Again we will reverse the list and traverse it from starting index \n");
    head = reverse(head);
    traverse1(head);
    return 0;
}