public void TestSubractCommand()
{
var c = new SubtractCommand(options);
var actualResult = c.Execute(new long[] { 4, 1, 1 });
Assert.Equal(2, actualResult);
}
static void Main(string[] args)
{
var receiver = new Calculator(345, 9945);
var addCommand = new AddCommand(receiver);
var subtractCommand = new SubtractCommand(receiver);
var multiplyCommand = new MultiplyCommand(receiver);
Console.WriteLine($"Add command result: {addCommand.Execute()}");
Console.WriteLine($"Subtract command result: {subtractCommand.Execute()}");
Console.WriteLine($"Multiply command result: {multiplyCommand.Execute()}");
Console.ReadKey();
}