CalculateTriangleArea

import java.math.BigDecimal;
import java.text.DecimalFormat;
import java.util.Scanner;

public class P06CalculateTriangleArea {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        double triangleBase = Double.parseDouble(scanner.nextLine());
        double triangleHeight = Double.parseDouble(scanner.nextLine());

        DecimalFormat df = new DecimalFormat("#.#################################");

        BigDecimal area = getTriangleArea(triangleBase, triangleHeight);
        System.out.println(df.format(area));

        //main ends here
    }

    static BigDecimal getTriangleArea(double triangleBase, double triangleHeight)
    {
        return BigDecimal.valueOf(1.0 * triangleBase * triangleHeight / 2) ;
    }

}