using System;

using System.Numerics;

public class Program

{

    public static void Main()

    {

        Vector3 a = new Vector3(4, 2, 1);

        Vector3 b = new Vector3(-3, 4, 5);

        Vector3 c = new Vector3(2, 6, 4);

        Vector3 d = new Vector3(-2, 3, -4);

        Vector3 g = new Vector3(-1, 5, -2);

        Console.WriteLine(c + b * 2);

        Console.WriteLine(2 * a - c * 3);

        Console.WriteLine(c / 2 + c - a * 2);

        Console.WriteLine("Illegal operation");

        Console.WriteLine(d + (a - b));

        Console.WriteLine(d + 2 * (d + g));

        Console.WriteLine((d + g) * 2);

        Console.WriteLine(Vector3.Dot(a, b));

        Console.WriteLine(a.Length());

        Console.WriteLine(Vector3.Normalize(c));

    }

}