static void Main(string[] args)
{
var additionStrategy = new AdditionStrategy();
var calculator = new PrimitiveCalculator(additionStrategy);
string line;
while ((line = Console.ReadLine()) != "End")
{
var tokens = line.Split();
if (tokens[0] == "mode")
{
var @operator = char.Parse(tokens[1]);
IStrategy strategy = CreateStrategy(additionStrategy, @operator);
calculator.ChangeStrategy(strategy);
}
else
{
var leftOperand = int.Parse(tokens[0]);
var rightOperand = int.Parse(tokens[1]);
var result = calculator.PerformCalculation(leftOperand, rightOperand);
Console.WriteLine(result);
}
}
}
private static IStrategy CreateStrategy(AdditionStrategy additionStrategy, char @operator)
{
IStrategy strategy = null;
switch (@operator)
{
case '+':
strategy = additionStrategy;
break;
case '-':
strategy = new SubtractionStrategy();
break;
case '*':
strategy = new MultiplicationStrategy();
break;
case '/':
strategy = new DivisionStrategy();
break;
}
return(strategy);
}
