DAS_2024_1/yakovleva_yulia_lab_2/App1/Program.cs

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string inputPath = Environment.GetEnvironmentVariable("DATA_PATH") ?? ".\\data";
        string outputPath = Environment.GetEnvironmentVariable("RESULT_PATH") ?? ".\\result";

        try
        {
            string[] files = Directory.GetFiles(inputPath);

            using (StreamWriter writer = new StreamWriter(Path.Combine(outputPath, "data.txt")))
            {
                foreach (string file in files)
                {
                    int lineCount = File.ReadAllLines(file).Length;
                    writer.WriteLine(lineCount);
                }
            }

            Console.WriteLine("Файл data.txt успешно создан");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Произошла ошибка: " + ex.Message);
        }
    }
}