using System;

using System.IO;

using LargeXlsx;

using NPOI.SS.UserModel;

using NPOI.XSSF.UserModel;

public class Program

{

    public static void Main()

    {

        using var stream = new MemoryStream();

        using (var xlsxWriter = new XlsxWriter(stream))

        {

            xlsxWriter

                .BeginWorksheet("Sheet 1")

                .BeginRow().Write("Name").Write("Location").Write("Height (m)")

                .BeginRow().Write("Kingda Ka").Write("Six Flags Great Adventure").Write(139)

                .BeginRow().Write("Top Thrill Dragster").Write("Cedar Point").Write(130)

                .BeginRow().Write("Superman: Escape from Krypton").Write("Six Flags Magic Mountain").Write(126);

        }

        stream.Seek(0, SeekOrigin.Begin);

        IWorkbook workbook;

        using (var file = new MemoryStream(stream.ToArray()))

        {

            workbook = new XSSFWorkbook(file);

        }

        Console.WriteLine(workbook.GetSheet("Sheet 1").FirstRowNum);

    }

}