public void Run()
{
Calculater calculater = new Calculater();
calculater.strategy = new SwingAddStrategy();
List <int> intList = new List <int>()
{
2, 3, 4, 5, 7, 8, 9
};
Console.WriteLine(calculater.DoMath(intList));
calculater.strategy = new AddStrategy();
Console.WriteLine(calculater.DoMath(intList));
}