static void Main(string[] args)
{
Stopwatch sw = new Stopwatch();
int[] array = Enumerable.Range(1, 7_000_000).ToArray();
sw.Start();
DataManipulator.FilterDigit(array, 7);
sw.Stop();
Console.WriteLine(nameof(DataManipulator.FilterDigit) + " elapsed time: " + sw.ElapsedTicks);
sw.Restart();
DataManipulator.FilterDigit1(array, 7);
sw.Stop();
Console.WriteLine(nameof(DataManipulator.FilterDigit1) + " elapsed time: " + sw.ElapsedTicks);
sw.Restart();
DataManipulator.FilterDigit2(array, 7);
sw.Stop();
Console.WriteLine(nameof(DataManipulator.FilterDigit2) + " elapsed time: " + sw.ElapsedTicks);
sw.Restart();
DataManipulator.FilterDigit3(array, 7);
sw.Stop();
Console.WriteLine(nameof(DataManipulator.FilterDigit3) + " elapsed time: " + sw.ElapsedTicks);
Console.ReadKey();
}