#include <iostream>

using namespace std;

//stack using array

class stackUsingArray

{

int* data;

//pointer le liye hain so that dynamically array ka size allocate kr den

int nextIndex;

//to traverse through array nextIndex le liye hain int type ka

int capacity;

//ise isliye initialize kiye hain taki stack ka size pata rhe

//basically ye help krta hai ye dekhne me ki hmara stack overflow to nhi kr rha

public:

//constructor

stackUsingArray(int totalSize){

//data name se array bana liye hain

data=new int[totalSize];

//starting me nextIndex ki value zero rakhenge

nextIndex=0;

capacity=totalSize;

//hmare stack ka utna hi capacity rahega jitna user ne paas kiya hai totalSize

}

//size funtion for returning size of stack

int sizeOfStack(){

return nextIndex;

//nextindex ki value jahan tk rahegi whi stack ki size rahegi

//kuki hm jb bhi koi element insert krte jate hain to nextindex ki size

//increase krte jate hain

}

int isEmpty(){

if(nextIndex==0)

return true;

else

return false;

}

//inserting an element

void push(int element){

if(nextIndex==capacity){

cout<<"stack is full ";

return;

}

data[nextIndex]=element;

nextIndex++;

}

//deleting an element

int pop(){

if(isEmpty()){

cout<<"Stack is empty"<<endl;

return INT_MIN;

}

nextIndex--;

return data[nextIndex];

}

//to see top element

int top()

{

if(isEmpty()){

cout<<"Stack is empty"<<endl;

return INT_MIN;

}

return data[nextIndex-1];

}

};

int main()

{

cout<<"Program started.."<<endl;

//stack-it is a abstract data type means hm isme specific order me hi data

//insert aur delete kr skte hain

stackUsingArray s(4);

s.push(10);

s.push(20);

s.push(30);

s.push(40);

cout<<s.top()<<endl;

cout<<s.pop()<<endl;

cout<<s.pop()<<endl;

cout<<s.pop()<<endl;

cout<<s.sizeOfStack()<<endl;

cout<<s.isEmpty()<<endl;

return 0;

}