using System.Collections.Generic;
public static IEnumerable<string> GetStuff(string input)
Console.WriteLine(input.Length);
yield return input.Substring(4, 40);
for (var i = 0; i < input.Length; i += 44)
yield return input.Substring(i + 2, 40);
public static void Main()
var input = "xxxx1234567890123456789012345678901234567890xx";
var input2 = "xx1234567890123456789012345678901234567890xxxx1234567890123456789012345678901234567890xxxx1234567890123456789012345678901234567890xxxx1234567890123456789012345678901234567890xx";
Console.WriteLine(string.Join("\r\n", GetStuff(input)));
Console.WriteLine(string.Join("\r\n", GetStuff(input2)));