Main.java

import Parser.*;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Map<String, Double> variables = new HashMap<>();

        while (true) {
            System.out.print("Enter expression: ");
            String input = scanner.nextLine();
            if (input.equalsIgnoreCase("exit")) break;

            try {
                Tokenizer tokenizer = new Tokenizer(input);
                Parser parser = new Parser(tokenizer);
                Node ast = parser.parseExpression(0);
                double result = ast.evaluate(variables);
                System.out.println("Result: " + result);
            } catch (Exception e) {
                System.out.println("Error: " + e.getMessage());
            }
        }
    }
}