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Java program to find the maximum and minimum elements in a stack

A stack is a basic data structure that follows the last-in first-out principle (also known as LIFO). There are many use cases for the stack, such as organizing function calls and undoing operations. Often, one may encounter the problem of finding the largest and smallest elements in the stack, and this article will demonstrate multiple ways to accomplish this task using Java. Understand the stack A stack is a linear data structure that allows operations only at one end, called the top. The main operations include: Push: Add elements to the top of the stack. Pop (Pop): Removes and returns to the top element of the stack. View (Peek): View the top element of the stack without removing it. IsEmpty: Check whether the stack is empty. Problem statement The goal is to determine the maximum and minimum elements in the stack. Given the stack

Feb 07, 2025 am 11:24 AM

Java

Convert ArrayList to HashMap in Java

The List interface in Java is a subinterface of the Collection interface, representing an ordered collection that allows duplicate elements. ArrayList is a common implementation class for the List interface. It is a dynamic array without prespecifying the size. HashMap is a class in the Java collection framework, used to store key-value pairs. Keys cannot be repeated and values can be repeated. This article will introduce several ways to convert ArrayList to HashMap: By iterating the ArrayList Using Java 8 Stream API Here are some examples: Input list: [1="1", 2="2", 3=&

Feb 07, 2025 am 11:23 AM

Java

Java program to sort the elements of the stack in descending order

This article demonstrates how to sort a stack's elements in descending order using Java. A stack, adhering to the Last-In-First-Out (LIFO) principle, is a fundamental data structure. Think of a browser's history; the most recently visited site is a

Feb 07, 2025 am 11:22 AM

Java

Primitive data type vs. Object data type in Java with Examples

Java variables are categorized by data types, defining their value and type. These fall into two main groups: primitive and object (non-primitive) data types. Primitive data types are predefined, with fixed sizes and types: byte, short, int, long, f

Feb 07, 2025 am 11:20 AM

Java

Java program to merge two arrays

This article demonstrates two Java methods for merging two arrays, ensuring the resulting array is sorted and contains no duplicates (in the second approach). The first method uses a straightforward array-based approach, while the second leverages a

Feb 07, 2025 am 11:19 AM

Java

ConcurrentModificationException while using Iterator in Java

In multithreaded Java environments, attempting to modify a collection while iterating over it using an iterator can lead to a ConcurrentModificationException. This exception arises because the collection's internal state becomes inconsistent. Here's

Feb 07, 2025 am 11:18 AM

Java

Convert ArrayList to LinkedHashMap in Java

A LinkedHashMap in Java maintains the insertion order of elements, unlike a regular HashMap. Converting an ArrayList to a LinkedHashMap requires assigning keys to each ArrayList element. The simplest approach uses the ArrayList index as the key. I

Feb 07, 2025 am 11:16 AM

Java

Delete middle element of a stack in Java

To delete the intermediate element of the stack, you first need to remove the element above the intermediate element. After removing the intermediate elements, the elements above them need to be restored to maintain the original order. This operation can be implemented using a recursive method, as described below. Due to the characteristics of the stack, we can only perform stack pressing and stacking operations on the top of the stack, so we cannot directly delete the intermediate elements of the stack. Steps to delete the middle element of the stack Step 1: Determine the position of the intermediate element First, you need to determine the intermediate element of the stack, the method is as follows: If the stack contains 9 elements (indexes 0 to 8), the intermediate element is at position 4. If the stack contains even numbers of elements (for example, 4 elements), the first of the two intermediate elements is deleted. If the stack contains only one element,

Feb 07, 2025 am 11:14 AM

Java

How do I get a platform-independent new line character?

When working with text in Java we often need to include new line characters to the format output properly. Different operating systems have different conventions for new line characters: Windows: This uses \r\n (Carriage Return Line Feed). Unix/Li

Feb 07, 2025 am 11:13 AM

Java

Java Program to Find the Volume of Cylinder

A cylinder is a three-dimensional geometric shape with two parallel circular base surfaces connected by curved surfaces. The volume of a cylinder can be calculated using mathematical formulas that consider its radius and height. Problem description In this tutorial, we will discuss how to calculate the volume of a given cylinder in Java using different methods. Cylinder volume formula The formula for the volume of the cylinder is as follows: Cylinder volume = π × r² × h in: r: The radius of the circular base surface. h: The body height of the cylinder. Example 1 **enter:** Radius = 5 units Height = 10 units **Output: ** Volume = 785.4 cubic units **illustrate:** Calculate volume using formula: volume

Feb 07, 2025 am 11:11 AM

Java