stack using array

#include <iostream>
using namespace std;

class Stack {
    int arr[10];
    int top;
public:
    Stack() { top = -1; }

    void push(int val) {
        if (top == 9)
            cout << "Stack Overflow!\n";
        else {
            arr[++top] = val;
            cout << val << " pushed to stack.\n";
        }
    }

    void pop() {
        if (top == -1)
            cout << "Stack Underflow!\n";
        else
            cout << arr[top--] << " popped from stack.\n";
    }

    void display() {
        cout << "Stack: ";
        for (int i = 0; i <= top; i++)
            cout << arr[i] << " ";
        cout << endl;
    }
};

int main() {
    Stack s;
    s.push(10);
    s.push(20);
    s.display();
    s.pop();
    s.display();

    cout << "\nTime Complexity: O(1)\nSpace Complexity: O(n)\n";
    return 0;
}