//
//  stack_using_linked_list.c
//  
//
//  Created by Bibhas Ghoshal on 18/04/23.
//

#include <stdio.h>

struct lifo
{
    int value;
    struct lifo *next;
};

typedef struct lifo stack;

void create (stack **top)
{
    *top = NULL;
    /* top points to NULL,
     indicating empty
     stack */
    
}

void push (stack **top, int element)
{
    stack *new;
    new = (stack *) malloc(sizeof(stack));
    if (new == NULL)
    {
        printf ("\n Stack is full \n");
        
        exit(-1);
    }
    new->value = element;
    new->next = *top;
    *top = new;
}


int pop (stack **top)
{
    int t;
    stack *p;
    if (*top == NULL)
    {
        printf ("\n Stack is empty\n");
        exit(-1);
    }
    else
    {
        t = (*top)->value;
        p = *top;
        *top = (*top)->next;
        free (p);
        return t;
    }
}

int isempty (stack *top)
{
    if (top == NULL)
        return (1);
    else
        return (0);
}

int main()
{
    stack *A, *B;
    create(&A); create(&B);
    push(&A,10);
    push(&A,20);
    push(&A,30);
    push(&B,100); push(&B,5);
    printf ("\n %d %d \n", pop(&A),pop(&B));
    printf ("\n %d %d \n", pop(&A),pop(&B));
    push (&A, pop(&B));
   // if (isempty(B))
   //     printf ("\n B is empty");
}