using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GeometryTasks
{
public class Vector
{
public double X;
public double Y;
}
public static class Geometry
{
public static double GetLength(Vector a)
{
return Math.Sqrt(a.X * a.X + a.Y * a.Y);
}
public static Vector Add( Vector a, Vector b)
{
return new Vector { X = a.X + b.X, Y = a.Y + b.Y } ;
}
}
}