Stack C++

#ifndef STACK_h
#define STACK_h

// Define the default capacity of the stack
#define SIZE 10
 
// A class to represent a stack
class stack
{
    int *arr;                       
    int top;
    int capacity;
 
public:
    stack(int size = SIZE);         // Constructor
    ~stack();                       // Destructor
 
    void push(int);    // Push onto the Stack
    int pop();         // Pop value from Stack
    int peek();        // See the top value on the Stack
    int size();        // Size of the Stack
    bool isEmpty();    // Check Stack is empty
    bool isFull();     // Check is Stack is full
};

#endif

#include<iostream>
using std::cout;
using std::endl;

#include "stack.h"

// Constructor to initialize the stack
stack::stack(int size)
{
    arr = new int[size];
    capacity = size;
    top = -1;            // index
}
 
// Destructor to free memory allocated to the stack
stack::~stack() {
    delete[] arr;
}

 void stack::push(int x)
{
    if (isFull())
    {
        cout << "Overflow Program Terminated" << endl;
    }
 
    cout << "Inserting " << x << endl;
    // Add value to the Stack
    arr[++top] = x;
}
 
// Utility function to pop a top element from the stack
int stack::pop()
{
    if (isEmpty())
    {
        cout << "Underflow Program Terminated " << endl;
    }
    cout << "Removing " << peek() << endl;

    // decrease stack size by 1 and (optionally) return the popped element
    return arr[top--];
}
 
// Utility function to return the top element of the stack
int stack::peek()
{
    if (!isEmpty()) {
        return arr[top];
    }
    else {
        cout << "Stack is Empty " << endl;
    }
}
 
// Utility function to return the size of the stack
int stack::size() {
    return top + 1;
}
 
// Utility function to check if the stack is empty or not
bool stack::isEmpty() {
    return size() == 0;   
}
 
// Utility function to check if the stack is full or not
bool stack::isFull() {
    return size() == capacity;
}

#include<iostream>
using std::cout;
using std::endl;

#include "stack.h"


int main()
{
    stack pt(3);
 
    pt.push(1);
    pt.push(2);
 
    pt.pop();
    pt.pop();
 
    pt.push(3);
 
    cout << "The top element is " << pt.peek() << endl;
    cout << "The stack size is " << pt.size() << endl;
 
    pt.pop();
 
    if (pt.isEmpty()) {
        cout << "The stack is empty\n";
    }
    else {
        cout << "The stack is not empty\n";
    }

}

Inserting 1
Inserting 2
Removing 2
Removing 1
Inserting 3
The top element is 3
The stack size is 1