using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Ingrese a: ");

        int a = Convert.ToInt16(Console.ReadLine());

        Console.WriteLine("Ingrese b: ");

        int b = Convert.ToInt16(Console.ReadLine());

        Console.WriteLine("Ingrese c: ");

        int c = Convert.ToInt16(Console.ReadLine());

        //Calcular el semiperimetro

        double ls = ((a+b+c) /2);

        //Calcular el area 

        double at = Math.Pow((ls * (ls - a) * (ls - b) * (ls - c)), 0.5 );

        //imprimir el resultado 

        Console.WriteLine("El area del triangulo es: {0}", at);

    }

}