371 - Triangle Stone

Triangle Stone

Time Limit: 1 sec


The Problem

You are given a Triangle Stone. Your task is to find the area of the stone.



The Input

The input file contains several lines. Each line contains three integers the length of the sides of the stone. All are ranged to 0 to 1000. The input file is terminated by EOF.


The Output

For each line of input output will print the area of the stone rounded to 2 decimal points in a separate line. Remember if the Triangle is invalid print 0.00


Sample Input

3 4 5

1 2 3


Sample Output







Problem Setter: Samia Safa Ahmed