import math

a = float(input("Enter the first side of the triangle: "))
b = float(input("Enter the second side of the triangle: "))
c = float(input("Enter the third side of the triangle: "))

if a + b > c and b + c > a and a + c > b:
    s = (a + b + c) / 2
    area = math.sqrt(s * (s-a) * (s-b) * (s-c))
    print("The area of the triangle is:", area)
else:
    print("These numbers do not form the sides of a triangle.")