import java.util.Scanner;

// Base class
class Shape {
    double calculateArea(double a) {
        return 0;
    }

    double calculateArea(double a, double b) {
        return 0;
    }
}

// Circle class
class Circle extends Shape {
    @Override
    double calculateArea(double radius) {
        return Math.PI * radius * radius;
    }
}

// Rectangle class
class Rectangle extends Shape {
    @Override
    double calculateArea(double length, double width) {
        return length * width;
    }
}

// Square class
class Square extends Shape {
    @Override
    double calculateArea(double side) {
        return side * side;
    }
}

public class AreaCalculator {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String shapeType = sc.nextLine();

        Shape shape=new Shape();
        double area = 0.0;

        switch (shapeType) {
            case "Circle":
                double radius = sc.nextDouble();
                if(radius<0){
                    System.out.println("Invalid input");
                    return;
                }
                Circle shape = new Circle();
                area = shape.calculateArea(radius);
                break;

            case "Rectangle":
                double length = sc.nextDouble();
                 if(length<0){
                    System.out.println("Invalid input");
                    return;
                }
                double width = sc.nextDouble();
                 if(width<0){
                    System.out.println("Invalid input");
                    return;
                }
                Rectangle shape = new Rectangle();
                area = shape.calculateArea(length, width);
                break;

            case "Square":
                double side = sc.nextDouble();
                 if(side<0){
                    System.out.println("Invalid input");
                    return;
                }
                Square shape = new Square();
                area = shape.calculateArea(side);
                break;

            default:
                System.out.println("Invalid input");
                return;
        }

        System.out.printf("%.2f\n", area);
    }
}