def areaTriangle(a, b, c):

	d = float(a + b + c / 2)
	area = sqrt((d * (d - a) * (d - b) * (d - c)))


	return area

def main():



	a = (input("Length of Side A of the triangle?"))

	b = (input("Length of Side B of the triangle?"))

	c = (input("Length of Side C of the triangle?"))

	print("The area of the triangle is " + str(areaTriangle(a,b, c)) + " .")


main()