C program to reverse the elements in the stack using recursion

				
					#include <stdio.h> 
#include <stdlib.h> 
struct node 
{ 
int a; 
struct node *next; 
};
void generate(struct node **);
void display(struct node *);
void stack_reverse(struct node **, struct node **); 
void delete(struct node **); 
int main() 
{
struct node *head = NULL; 
generate(&head);
printf("\nThe sequence of contents in stack\n"); 
display(head);
printf("\nInversing the contents of the stack\n"); 
if (head != NULL) 
{ 
stack_reverse(&head, &(head->next));
}
printf("\nThe contents in stack after reversal\n"); 
display(head);
delete(&head);
return 0;
}
void stack_reverse(struct node **head, struct node **head_next)
{
struct node *temp; 
if (*head_next != NULL)
{ 
temp = (*head_next)->next; 
(*head_next)->next = (*head); 
*head = *head_next; 
*head_next = temp; 
stack_reverse(head, head_next); 
}
}
void display(struct node *head) 
{
if (head != NULL)
{
printf("%d ", head->a); 
display(head->next); 
}
} 
void generate(struct node **head)
{
int num, i;
struct node *temp; 
printf("Enter length of list: "); 
scanf("%d", &num);
for (i = num; i > 0; i--) 
{ 
temp = (struct node *)malloc(sizeof(struct node));
temp->a = i;
if (*head == NULL) 
{
*head = temp;
(*head)->next = NULL;
}
else
{ 
temp->next = *head; 
*head = temp; 
}
}
}
void delete(struct node **head) 
{
struct node *temp;
while (*head != NULL) 
{
temp = *head; *head = (*head)->next;
free(temp); 
}
}
				
			
INPUT/OUTPUT:

Enter length of list: 10

The sequence of contents in stack

1 2 3 4 5 6 7 8 9 10

Reversing the contents of the stack

The contents in stack after reversal

10 9 8 7 6 5 4 3 2 1

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