AreaOfFigures

import java.text.DecimalFormat;
import java.util.DoubleSummaryStatistics;
import java.util.Scanner;

/**
 * Created by entropy on 3/23/2017.
 */
public class areaFigures {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String figure = scanner.nextLine();


        Double area = 0.0;

        if (figure.equalsIgnoreCase("square")) {
            System.out.println("Input side");
            Double side = Double.parseDouble(scanner.nextLine());
            area = side * side;
        } else if (figure.equalsIgnoreCase("rectangle")) {
            System.out.println("Input side1");
            Double side1 = Double.parseDouble(scanner.nextLine());
            System.out.println("Input side2");
            Double side2 = Double.parseDouble(scanner.nextLine());
            area = side1 * side2;
        } else if (figure.equalsIgnoreCase("circle")) {
            System.out.println("Input radius");
            Double radius = Double.parseDouble(scanner.nextLine());
            area = Math.PI * radius * radius;
        } else if (figure.equalsIgnoreCase("triangle")) {
            System.out.println("Input side");
            Double side = Double.parseDouble(scanner.nextLine());
            System.out.println("Input height");
            Double height = Double.parseDouble(scanner.nextLine());
            area = (side * height) / 2;
        }
        //  System.out.printf("%.3f", area);

        DecimalFormat df = new DecimalFormat("#.###");
        System.out.println(df.format(area));
    }
}