Stacks.java

class Stack {
    int maxSize;
    int[] arr;
    int top;

    Stack(int size) {
        maxSize = size;
        arr = new int[maxSize];
        top = -1;
    }

    void insert(int value) {
        if (top == maxSize - 1) return;
        arr[++top] = value;
    }

    void delete() {
        if (top == -1) return;
        top--;
    }

    void display() {
        if (top == -1) {
            System.out.println("Stack is empty");
            return;
        }
        for (int i = 0; i <= top; i++) {
            System.out.print(arr[i] + " ");
        }
        System.out.println();
    }

    void getsize() {
        System.out.println( top + 1);
    }
    boolean isEmpty() {
        return top == -1;
    }
}

public class Stacks {
    public static void main(String[] args) {
        Stack s = new Stack(5);
        s.display();
        s.insert(5);
        s.insert(7);
        s.insert(6);
        s.display();
        s.delete();
        s.display();
        s.insert(8);
        s.insert(9);
        s.display();

        s.getsize(); // size
        System.out.println(s.isEmpty()); // false


    }
}