abonty_stack

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

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

struct stack* top=NULL;//GLOBAL VARIABLE


bool is_empty()
{
    return (top==NULL);
}

void push(int data)
{

    struct stack *temp=(struct stack*)malloc(sizeof(struct stack ));
    temp->data=data;
    if(is_empty())
    {
        top=temp;
        temp->next=NULL;
    }
    else
    {
        temp->next=top;
        top=temp;
    }

}


void pop()
{

    if(is_empty())
    {
        printf("The stack is empty\n");
        return;
    }

    struct stack *temp=top;

    top=temp->next;

    temp->next=NULL;


}

void traverse()
{
    struct stack *ptr=top;
    if(is_empty())
    {
        printf("The stack is empty.\n\n");
        return;
    }


    while(ptr!=NULL)
    {
        printf("%d",ptr->data);
        printf(" ");
        ptr=ptr->next;
    }
    printf("\n");
}

int size()
{
    int length=0;
    struct stack* temp=top;
    while(temp!=NULL)
    {
        length++;
        temp=temp->next;
    }

  return length;
}

 int top_element()
{
    int x=top->data;
    return x;
}

void print()
{
    printf("Stack Operations.\n");
    printf("1. Insert into stack (Push operation).\n");
    printf("2. Delete from stack (Pop operation).\n");
    printf("3. Print top element of stack.\n");
    printf("4. Check if stack is empty.\n");
    printf("5. Traverse stack.\n");
    printf("6. Size.\n");
    printf("7. Exit.\n");
    printf("Enter your choice.\n");
}

int main()
{
    int choice;
    while(1)
    {
        print();
        scanf("%d",&choice);
        if(choice==1)
        {
             printf("Enter the data you want to insert:");
             int data;
             scanf("%d",&data);
             push(data);
        }
        else if(choice==2)
        {
            pop();
        }
        else if(choice==3)
        {
            if(is_empty())
            {
                printf("The stack is empty\n");

            }
            else
            {
                int topelm=top_element();
                printf("%d\n",topelm);
            }
        }
        else if(choice==4)
        {
            if(is_empty())
            {
                printf("The stack is empty\n");
            }
            else
            {
                printf("The stack isn't empty\n");
            }
        }
        else if(choice==5)
        {
            traverse();
        }
        else if(choice==6)
        {
           int siz=size();
            printf("size is %d\n",siz);
        }
        else if(choice==7)
        {
            break;

        }

    }
}