using System.Text.RegularExpressions; namespace Day9; public partial class Parser { [GeneratedRegex(@".*")] private partial Regex LineMatch(); public IEnumerable Parse(string inputFile) { using var reader = File.OpenText(inputFile); while (!reader.EndOfStream) { var line = reader.ReadLine()!; var numbers = line.Split(' ').Select(long.Parse).ToArray(); yield return new Sequence(numbers); } } }