Algorithm exercise: Module that evaluates a string that contains an arithmetic expression

# Infix Calculator

Welcome to the Infix Calculator project! This Java program allows you to evaluate mathematical expressions written in infix notation. It can handle basic arithmetic operations, parentheses, and negative numbers.

## Table of Contents
- [Introduction](#introduction)
- [Getting Started](#getting-started)
  - [Prerequisites](#prerequisites)
  - [Installation](#installation)
- [Usage](#usage)
- [Examples](#examples)
- [Main Methods](#main-methods)
- [Testing](#testing)
- [Contributing](#contributing)
- [License](#license)

## Introduction

In mathematics, infix notation is a common way of representing mathematical expressions, where operators are placed between operands. The Infix Calculator project takes infix expressions and evaluates them, providing the result.

## Getting Started

### Prerequisites

Make sure you have the following prerequisites installed on your system:

- Java (JDK 8 or higher)

### Installation

1. Clone the repository to your local machine:

   ```bash
   git clone https://github.com/yourusername/infix-calculator.git

2. Navigate to the project directory:

   cd infix-calculator

3. Compile the Java code:

   javac EvaluateMathematicalExpression.java

To use the Infix Calculator, you can create an instance of the EvaluateMathematicalExpression class and call the evaluate method with your mathematical expression as a string. Here's a basic example:

EvaluateMathematicalExpression evaluator = new EvaluateMathematicalExpression();
double result = evaluator.evaluate("5 + 3 * (10 - 2) / 4");
System.out.println("Result: " + result);

Here are some example expressions you can try:

• 5 + 3 * (10 - 2) / 4
• -(4 + 2) * -3
• 12 * 123 / (-5 + 2)

• Determines if a given string is a numeric operand.
• Returns true if the input is a valid numeric value, false otherwise.

• Checks if a given string is a valid operator.
• Returns true if the input is one of the supported operators (+, -, *, /), false otherwise.

• Tokenizes and normalizes a mathematical expression.
• Returns a list of strings representing the individual elements of the expression with spaces removed and additional spaces added around parentheses and operators.

• Evaluates a given infix mathematical expression and returns the result as a double.
• Takes an infix expression as input and returns the calculated result.

• Performs the core logic for connecting and pushing operators and nodes.
• Handles operator precedence, balancing, and parenthesized expressions.
• Returns true if the operation succeeded, false otherwise.

• Converts an infix expression into a syntax tree for evaluation.
• Uses stacks to manage operators and nodes during the conversion.
• Returns the root of the syntax tree.

The project includes JUnit tests to ensure the correctness of the calculator. You can run the tests using your preferred IDE or build tool.

Contributions are welcome! If you find any issues or have suggestions for improvements, please open an issue or submit a pull request.

🚀 Happy calculating! 🧮