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

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

static void reverse(struct Node** head_ref)
{
    struct Node* prev = NULL;
    struct Node* current = *head_ref;
    struct Node* next = NULL;
    while (current != NULL) 
    {
        next = current->next;
        current->next = prev;
        prev = current;
        current = next;
    }
    *head_ref = prev;
}
  
void push(struct Node** head_ref, int new_data)
{
    struct Node* new_node= (struct Node*)malloc(sizeof(struct Node));
    new_node->data = new_data;
    new_node->next = (*head_ref);
    (*head_ref) = new_node;
}

void printList(struct Node* head)
{
    struct Node* temp = head;
    while (temp != NULL)
    {
        printf("%d  ", temp->data);
        temp = temp->next;
    }
}

int main()
{

    struct Node* head = NULL;
  
    push(&head, 20);
    push(&head, 4);
    push(&head, 15);
    push(&head, 85);
  
    printf("Given linked list\n");
    printList(head);
    reverse(&head);
    printf("\nReversed Linked list \n");
    printList(head);
    getchar();
}
