using System;

​

public readonly struct Vector {

    private readonly int x;

    private readonly int y;

    public Vector(int X, int Y) {

        x = X;

        y = Y;

    }

    public static Vector operator +(Vector a, Vector b)

        => new Vector(a.x + b.x, a.y + b.y);

    public static Vector operator -(Vector a, Vector b)

        => new Vector(a.x - b.x, a.y - b.y);

    public static Vector operator *(Vector a, int scalar) 

        => new Vector(a.x * scalar, a.y * scalar);

    public override string ToString() => $"({x}, {y})";

}

public class Program

{

    public static void Main()

    {

        var one = new Vector(10, 20);

        var two = new Vector(5, 10);

        Console.WriteLine(one + two);

        Console.WriteLine(one - two);

        Console.WriteLine(one * 5);

    }

}