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import java.util.Scanner;

/**
 *
 * @author Алла
 */
public class Calculator {

    Scanner in = new Scanner(System.in);
    private OperationFactory operationFactory;

    public Calculator(OperationFactory operationFactory) {
        this.operationFactory = operationFactory;
    }

    public void exec() {
        while (true) {
  
       
                System.out.println("Aргумент 1:");
                double arg1 = Double.parseDouble(in.nextLine());

                System.out.println("Операция:");
                String op = in.nextLine();

                System.out.println("Aргумент 2:");
                double arg2 = Double.parseDouble(in.nextLine());

                double result = operationFactory.getOpInstance(op).exec(arg1, arg2);

                System.out.println("Результат:" + result);
            
           

        }
    }

    public static void main(String[] args) {
        MyOpFactory operationFactory = new MyOpFactory();
        Calculator calculator = new Calculator(operationFactory);
        calculator.exec();
    }
}