using Lesson6.Classes; namespace Lesson6 { class Program { static void Main(string[] args) { Calculator calc = new Calculator(); // subscribe to the event calc.CalculationPerformed += result => Console.WriteLine($"Result: {result}"); while (true) { Console.Write("Enter expression (e.g. 2 + 2) or exit: "); string? expression = Console.ReadLine(); if (expression == null) continue; if (expression == "exit") break; calc.Calculate(expression); } } } }