Stack Algorithm:
The stack can be easily implemented using an Array or a Linked List. Arrays are quick but are limited in size and Linked List requires overhead to allocate, link, unlink, and deallocate, but is not limited in size. Here we will implement Stack using array.
  1. In computer science, a stack is an abstract data type that serves as a collection of elements.
  2. Recursion uses a stack and if you want total control or to avoid some system overhead you can use your own.
  3. Converting infix to postfix notation
  4. Do not have a fixed size
  5. Do not consume a fixed amount of memory
public class Stack {

    private int arra[];
    private int top;
    private int capacity;

    //Constructor for initialize Stack
    Stack(int size) {
        arra = new int[size];
        top = -1;
        capacity = size;
    }
 
    // Add value in stack
    public void push(int x) {
        if (isful()) {
            System.out.println("Overflow\nProgram Terminated");
            System.exit(1);
        }
        System.out.println("Insert The Value " + x);
        arra[++top] = x;
    }

    // Remove value from Stack
    public int pop() {
        if (isempty()) {
            System.out.println("Stack is Underflow\nProgram Terminated");
            System.exit(1);
        }
        System.out.println("Remove The Vallue " + peek());
        return arra[--top];
    }

    // Retrive Top Value in Stack
    public int peek() {

        if (!isempty()) {
            return arra[top];

        } else {
            System.exit(1);
        }
        return -1;
    }

    //Check the Stack full or not. If full then return true
    public boolean isful() {
        return top == capacity - 1;
    }

    // Check Stack is Empty
    public boolean isempty() {
        return top == -1;
    }

    // Stack Size
    public int size() {

        return top + 1;
    }

    public static void main(String[] args) {

        Stack st = new Stack(5);
        st.push(1); // Inserting The Element of stack
        st.push(2); //Inserting The Element of Stack
        st.push(3);
        System.out.println("Top element of stack " + st.peek());
        st.pop(); // Removing The Element of Stack

        // Check Stack is Empty or not
        if (st.isempty()) {
            System.out.println("Stack is Empty");
        } else {
            System.out.println("Stack is not empty");
        }

        // Stack Size 
        System.out.println("The Stack Size is " + st.size());
    }
}

Output:
Insert the value 1
Insert the value 2


Insert the value 3


Top element of stack 3


Remove the value 3


Stack is not empty


The Stack size 2