public static void Main()
{
PrimitiveCalculator calculator = new PrimitiveCalculator();
string[] input = Console.ReadLine().Split();
while (input[0] != "End")
{
if (input[0] == "mode")
{
calculator.changeStrategy(char.Parse(input[1]));
}
else
{
int firstOperand = int.Parse(input[0]);
int secondOperand = int.Parse(input[1]);
Console.WriteLine(calculator.performCalculation(firstOperand, secondOperand));
}
input = Console.ReadLine().Split();
}
}
