DSA-lab3(b)-stackWithUSER-INPUT

import java.util.Scanner;
public class Main {
    public int max;
    public int[] arr;
    public int tos = -1;

    public Main(int max) {
        this.max = max;
        arr = new int[max];
    }

    public void push(int data) {
        if (tos == max - 1) {
            System.out.println("Overflow");
            return;
        }
        tos++;
        arr[tos] = data;
        System.out.println("Push: " + data);
    }

    public void pop() {
        if (tos == -1) {
            System.out.println("Underflow");
            return;
        }
        int popd = arr[tos];
        tos--;
        System.out.println("Pop: " + popd);
    }

    public void peep() {
        if (tos == -1) {
            System.out.println("Stack is empty");
            return;
        }
        System.out.println("Top element (peep) " + arr[tos]);
    }

    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        System.out.println("Enter max size of stack: ");
        int maxSize = sc.nextInt();
        Main stack=new Main(maxSize);

        while (true) {
            System.out.println("\nChoose operation:");
            System.out.println("1 - Push");
            System.out.println("2 - Pop");
            System.out.println("3 - Peep");
           
            int choice = sc.nextInt();
            switch (choice) {
                case 1:
                    System.out.print("Enter value to push: ");
                    int val = sc.nextInt();
                    stack.push(val);
                    break;
                case 2:
                    stack.pop();
                    break;
                case 3:
                    stack.peep();
                    sc.close();
                    return;
                default:
                    System.out.println("Invalid choice. Try again.");
            }
        }
    }
}