triangle.rb

# Triangle Project Code.

# Triangle analyzes the lengths of the sides of a triangle
# (represented by a, b and c) and returns the type of triangle.
#
# It returns:
#   :equilateral  if all sides are equal
#   :isosceles    if exactly 2 sides are equal
#   :scalene      if no sides are equal
#
# The tests for this method can be found in
#   about_triangle_project.rb
# and
#   about_triangle_project_2.rb
#
def triangle(a, b, c)
  raise TriangleError, "Sides have to be greater than zero" if (a == 0) || (b == 0) || (c == 0)
  raise TriangleError, "Sides have to be a postive number" if (a < 0) || (b < 0) || (c < 0)
  raise TriangleError, "Two sides can never be less than the sum of one side" if ((a + b) < c) || ((a + c) < b) || ((b + c) < a)
  raise TriangleError, "Two sides can never be equal one side" if ((a + b) ==  c) || ((a + c) ==  b) || ((b + c) ==  a)
  if (a == b && b == c && a == c)
    return :equilateral
  end
  if (a == b || b == c || a == c)
    return :isosceles
  end
  if (a != b && a!= c && b!= c)
    return :scalene
  end
end

# Error class used in part 2.  No need to change this code.
class TriangleError < StandardError
end