Which of these two ways to write this program is "better"?

[psx2514]

I wrote two versions of a simple program that gives the area of a triangle using Heron's formula. Will someone tell me which version is better, and explain why. Thanks.
This is the first version:

import java.util.Scanner;
import java.text.DecimalFormat;
public class AreaOfTriangle 
{
	public static void main(String[] args)
	{
		double sideA, sideB, sideC, s, area;
		Scanner scan = new Scanner(System.in);
		
		
		System.out.println("This program finds the area of a triangle" +
				" using Heron's formula.\n");
		System.out.print("Enter the length of the first side: ");
		sideA = scan.nextDouble();
		System.out.print("Enter the length of the second side: ");
		sideB = scan.nextDouble();
		System.out.print("Enter the length of the third side: ");
		sideC = scan.nextDouble();
		s = (sideA+sideB+sideC)/2;
		area = Math.sqrt(s*(s-sideA)*(s-sideB)*(s-sideC));
		DecimalFormat fmt = new DecimalFormat("0.###");
		Double new_area = new Double(fmt.format(area));
		System.out.println("The area is: " + new_area);
		
		
	}

}

and this is the second version:

import java.util.Scanner;
import java.text.DecimalFormat;
public class AreaOfTriangle 
{
	public static void main(String[] args)
	{
		double sideA, sideB, sideC, s, area;
		Scanner scan = new Scanner(System.in);
		
		
		System.out.println("This program finds the area of a triangle" +
				" using Heron's formula.\n");
		System.out.print("Enter the length of the first side: ");
		sideA = scan.nextDouble();
		System.out.print("Enter the length of the second side: ");
		sideB = scan.nextDouble();
		System.out.print("Enter the length of the third side: ");
		sideC = scan.nextDouble();
		s = (sideA+sideB+sideC)/2;
		area = Math.sqrt(s*(s-sideA)*(s-sideB)*(s-sideC));
		DecimalFormat fmt = new DecimalFormat("0.###");
		area = (Double.parseDouble(fmt.format(area)));
		System.out.println("The area is: " + area);
		
		
	}

}

[JosAH]

You probably don't want to read this but Heron's formula as used in both version is numerically unstable for triangles with one small angle; I suggest rewriting it as a more stable version (Google is your friend here).

kind regards,

Jos

[Tolls]

DecimalFormat fmt = new DecimalFormat("0.###");
Double new_area = new Double(fmt.format(area));
System.out.println("The area is: " + new_area);

What is the purpose of this?
If it's to format the output then do that...don't format, reassign to a double, then print the double, which will in all likelihood not be the format you want.

[kjkrum]

Uh... what's the difference between the two versions?

[Tolls]

Uh... what's the difference between the two versions?

Oh good.
I didn't want to say anything yesterday in case I was missing something obvious!
:)

[psx2514]

The assignment asked to use Heron's formula.
Look at lines 20-24. You'll see the difference between the two programs there.
Now, which one is better?

[Tolls]

Oh right.
But they both do pointless formatting and parsing...so neither?

[JosAH]

The assignment asked to use Heron's formula.
Look at lines 20-24. You'll see the difference between the two programs there.
Now, which one is better?

But there is a stable version for Heron's formula; Google for it and use that one and formatting a double and parsing the result afterwards again is just a no no.

kind regards,

Jos