package com.sarvesh.javabasics; public class CustomStack { private int[] arr; private int top; private int capacity; public CustomStack(int size) { this.arr = new int[size]; this.capacity = size; this.top = -1; } public void push(int x) { if (top == capacity - 1) { System.out.println("System Crash: Stack Overflow"); return; } arr[++top] = x; } public int pop() { if (top == -1) { System.out.println("System Crash: Stack Underflow"); return -1; } return arr[top--]; } public int peek() { if (top == -1) return -1; return arr[top]; } public static void main(String[] args) { CustomStack engine = new CustomStack(5); engine.push(10); engine.push(20); System.out.println("Popped: " + engine.pop()); System.out.println("Peek: " + engine.peek()); } }