// Program: Stack Implementation Using Arrays

// Topic: Stack Data Structure

// Description: Implements a stack using an integer array with basic operations — `push()`, `pop()`, and `peek()`.

// Includes utility methods `isEmpty()` and `isFull()` to check stack conditions and prevent underflow or overflow.

// Demonstrates stack behavior (LIFO – Last In, First Out) and performs sample push operations in the `main()` method.

package stack;

/**

*

* @author Samim

*/

public class Stack {

private int maxSize;

private int[] stackArray;

private int top;

public Stack(int size) {

this.maxSize = size;

this.stackArray = new int[maxSize];

this.top = -1;

}

public void push(int value) {

if (isFull()) {

System.out.println("Stack is full. Cannot push " + value);

return;

}

top++;

stackArray[top] = value;

}

public int pop() {

if (isEmpty()) {

System.out.println("Stack is empty. Cannot pop.");

return -1;

}

int value = stackArray[top];

top--;

return value;

}

public int peek() {

if (isEmpty()) {

System.out.println("Stack is empty. Cannot peek.");

return -1;

}

return stackArray[top];

}

public boolean isEmpty() {

return (top == -1);

}

public boolean isFull() {

return (top == maxSize - 1);

}

public static void main(String[] args){

//The no of input defines which method will be invoked

Stack stack =new Stack(10);

stack.push(50);

stack.push(70);

// System.out.println("Peek: " + stack.peek());

// System.out.println("Pop: " + stack.pop());

// System.out.println("Peek: " + stack.peek());

stack.push(40);

stack.push(50);

stack.push(60); // This will cause overflow

}

}