public class Calc2 {
	public static void main(String[] args)
  {
	double x;
	double y;
	double result;
	x=Double.parseDouble(args[0]);
	y=Double.parseDouble(args[2]);
	if (args[1].equals("add")) result = x+y;
	else if(args[1].equals("sub")) result = x-y;
	else if (args[1].equals("mul")) result = x*y;
	else if (args[1].equals("div")) result = x/y;
		//else System.out.println("Wrong Input");
	
	System.out.println(result);

  }
}