Calculate Triangle Area with Heron's Formula

package edu.berkeley.cs;
 
/**
 * Compute the area of a triangle using Heron's Formula. Code and values from Prof W. Kahan and Joseph D. Darcy. See http://www.cs.berkeley.edu/~wkahan/JAVAhurt.pdf. Derived from listing in Rick
 * Grehan's Java Pro article (October 1999). Simplified and reformatted by Ian Darwin.
 */
public class Heron {
    public static void main(String[] args) {
	// Sides for triangle in float
	float af, bf, cf;
	float sf, areaf;
 
	// Ditto in double
	double ad, bd, cd;
	double sd, aread;
 
	// Area of triangle in float
	af = 12345679.0f;
	bf = 12345678.0f;
	cf = 1.01233995f;
 
	sf = (af + bf + cf) / 2.0f;
	areaf = (float) Math.sqrt(sf * (sf - af) * (sf - bf) * (sf - cf));
	System.out.println("Single precision: " + areaf);
 
	// Area of triangle in double
	ad = 12345679.0;
	bd = 12345678.0;
	cd = 1.01233995;
 
	sd = (ad + bd + cd) / 2.0d;
	aread = Math.sqrt(sd * (sd - ad) * (sd - bd) * (sd - cd));
	System.out.println("Double precision: " + aread);
    }
}