static void Main(string[] args)
{
Console.Write("Enter X:");
double entryX = double.Parse(Console.ReadLine());
Console.Write("Enter Y:");
double entryY = double.Parse(Console.ReadLine());
Console.Write("Enter Z:");
double entryZ = double.Parse(Console.ReadLine());
Console.Write("Enter X1:");
double entryX1 = double.Parse(Console.ReadLine());
Console.Write("Enter Y1:");
double entryZ1 = double.Parse(Console.ReadLine());
Console.Write("Enter Z1:");
double entryY1 = double.Parse(Console.ReadLine());
var a = new Point3D(entryX, entryY, entryZ);
var b = new Point3D(entryX1, entryY1, entryZ1);
Console.WriteLine($"{DistanceCalculator.DistanceBetweenPoint3D(a, b):F8}");
}