import java.util.Scanner;
 
class GeometricShapes {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int choice;
 
        do {
            System.out.println("\n--- Geometric Shapes Calculator ---");
            System.out.println("1. Rectangle");
            System.out.println("2. Circle");
            System.out.println("3. Triangle");
            System.out.println("4. Exit");
            System.out.print("Enter your choice: ");
            choice = sc.nextInt();
 
            switch (choice) {
                case 1:
                    // Rectangle
                    System.out.print("Enter length: ");
                    double length = sc.nextDouble();
                    System.out.print("Enter width: ");
                    double width = sc.nextDouble();
 
                    double rectPerimeter = 2 * (length + width);
                    double rectArea = length * width;
 
                    System.out.printf("Rectangle Perimeter = %.2f%n", rectPerimeter);
                    System.out.printf("Rectangle Area = %.2f%n", rectArea);
                    break;
 
                case 2:
                    // Circle
                    System.out.print("Enter radius: ");
                    double radius = sc.nextDouble();
 
                    double circlePerimeter = 2 * Math.PI * radius;
                    double circleArea = Math.PI * radius * radius;
 
                    System.out.printf("Circle Perimeter (Circumference) = %.2f%n", circlePerimeter);
                    System.out.printf("Circle Area = %.2f%n", circleArea);
                    break;
 
                case 3:
                    // Triangle
                    System.out.print("Enter side 1: ");
                    double a = sc.nextDouble();
                    System.out.print("Enter side 2: ");
                    double b = sc.nextDouble();
                    System.out.print("Enter side 3: ");
                    double c = sc.nextDouble();
 
                    double triPerimeter = a + b + c;
                    double s = triPerimeter / 2; // semi-perimeter for area
                    double triArea = Math.sqrt(s * (s - a) * (s - b) * (s - c)); // Heron's formula
 
                    System.out.printf("Triangle Perimeter = %.2f%n", triPerimeter);
                    System.out.printf("Triangle Area = %.2f%n", triArea);
                    break;
 
                case 4:
                    System.out.println("Exiting program. Goodbye!");
                    break;
 
                default:
                    System.out.println("Invalid choice! Please select 1-4.");
            }
        } while (choice != 4);
 
        sc.close();
    }
}