using System;

namespace ConsoleApp21
{
    class Program
    {
        static void Main(string[] args)
        {
            double[] va = new double[] { 1, 2, 3, 11 };
            double[] vb = new double[] { 4, 5, 6, 22 };
            double[] vc = Add(va, vb);

            Print(va);
            Print(vb);
            Print(vc);
        }
        private static double[] Add(double[] vectorA, double[] vectorB)
        {
            if (vectorA.Length != vectorB.Length)
            {
                return null;
            }

            double[] vectorC = new double[vectorA.Length];

            for (int i = 0; i < vectorC.Length; i++)
            {
                vectorC[i] = vectorA[i] + vectorB[i];
            }

            return vectorC;
        }

        private static void Print(double[] vector)
        {
            Console.Write("{ ");

            foreach (double d in vector)
            {
                Console.Write(d + " ");
            }

            Console.WriteLine("}");
        }
    }
}