DailyProgrammerStuff.cs

using System;
using System.Globalization;

namespace YearCalc
{
	class Program
	{
		static void Main(string[] args)
		{
			Console.Write("Input date (e.g. \"31.05\"): ");
			DateTime blah = DateTime.Parse(Console.ReadLine(), CultureInfo.GetCultureInfo("de"));

			int nt = blah.Day;
			int nm = GetNM(blah);

			Console.Write("For what yearhunded (e.g. 2000 for the current) the dates shall the dates be outputted: ");
			int jh = int.Parse(Console.ReadLine()) / 100;

			int njh = 6 - (jh % 4) * 2;
			int x = 6 - (nt + nm + njh) % 7;

			for (int i = 0; i < 99; i += 7 )
			{
				int njz = x + i;
				int jz = (int)Math.Ceiling(njz / 1.25);
				int njzcheck = (int)(jz / 4) + jz;

				if(njz == njzcheck) //Yay, found a year! Need to chech since I only have a function jz -> njz, and the function isn't surjective, so imma check back. 
				{
					string date = blah.Day + "." + blah.Month + "." + jh + jz.ToString("00");
					Console.Write(date);
					Console.WriteLine(" " + DateTime.Parse(date, CultureInfo.GetCultureInfo("de")).DayOfWeek);
				}

			}

			Console.ReadLine();
		}

		static int[] nmtable2 = { 6, 2, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5 };
		static int[] nmtable = { 0, 3, 3, 6, 1, 4, 6, 2, 5, 0, 3, 5 };
		static int GetNM(DateTime dateTime)
		{
			if (dateTime.Year % 4 == 0) //leap year handling.
				return nmtable2[dateTime.Month - 1];
			else
				return nmtable[dateTime.Month - 1];

		}
	}
}